Acta Polytechnica https://doi.org/10.14311/AP.2025.65.0119 Acta Polytechnica 65(1):119–135, 2025 © 2025 The Author(s). Licensed under a CC-BY 4.0 licence Published by the Czech Technical University in Prague A STUDY OF X-RAY POINT SOURCES IN HEILES CLOUDS 1 AND 2 Nóra Vargaa,∗, András Péter Joóa, Bendegúz Koncza,b a Eötvös Loránd University, Department of Astronomy, Pázmány Péter sétány 1/A, 1117 Budapest, Hungary b Doctoral School of Physics at University of Debrecen, Bem tér 18/B, 4026 Debrecen, Hungary ∗ corresponding author: varganora43@gmail.com Abstract. Star formation takes place in the coldest parts of molecular clouds, beginning in the densest, collapsing regions of filaments. As pre-main sequence stars are luminous X-ray emitters, X-ray point sources can serve as effective tracers of YSOs. In our study, we examined the distribution of X-ray point sources in two nearby molecular clouds: Heiles Cloud 2 (HCL 2), a ring-like molecular cloud complex in the Taurus region, and Heiles Cloud 1 (LDN 1251), a cometary-shaped dark molecular cloud. By incorporating the latest YSO catalogue from Gaia DR3, we analysed how YSO positions compare to the structure of the interstellar medium (ISM) and found that the sources are primarily aligned just outside the densest regions. Additionally, we compared the positions with the magnetic field structure and found no clear correlation at the given resolution. Keywords: ISM, YSO, polarisation, magnetic field. 1. Introduction Star formation takes place in the coldest, densest parts of the interstellar medium (ISM), in the molecular clouds. The term “cloud” is used to refer to structures in the interstellar medium that are separated from their surroundings by a sharp change in some physical or chemical property. The ISM is highly filamentary, and these filaments have been recognized as important environments for star formation and the growth of new stars in these dense, active regions [1]. In wavelength ranges where strong, diffuse galactic background radi- ation dominates, such as in the far-infrared range, we can use the absorption of dust against the continuum radiation to study the structure of clouds. Examples of this methodology are the works of Bacmann et al. [2] and Stutz et al. [3], which demonstrated that detailed images of the internal structure of clouds and cores can be obtained using this technique. The Herschel Space Telescope has mapped the sky at far-infrared and submillimetre wavelengths providing data on the highly structured ISM [4]. Molecular clouds have high density cores, which are the densest regions where gravity pulls the gas together. Star formation begins with the gravitational collapse of dense, rotating, magnetic molecular cloud cores. Due to angular momentum conservation, this process is always accompanied by the formation of circumstellar disks (e.g. Shu, Adams & Lizano 1987), sometimes still embedded in their envelope.The evolu- tion of young stars in the first few million years after they emerge from their protostellar dusty envelopes is characterised by the presence of circumstellar disks and intense magnetic fields. Pre-main sequence stars are luminous X-ray sources due to the accretion pro- cess. Young stars emit X-rays with a luminosity sev- eral orders of magnitude higher than that of older field stars (Preibisch & Feigelson 2005 [5]). As a result, X-ray observations have proven to be a highly effec- tive method for identifying stellar members of young star-forming complexes, even in highly contaminated fields. This approach is relatively unbiased by the presence or absence of circumstellar disks (e.g., [6, 7]). These observations of star-forming regions allow for the study of high-energy processes in YSOs, which are of great importance for our understanding of the star formation process. However there are a number of other types of X-ray point sources, including extra- galactic ones. In our pilot study, we are attempting a comparative study of the distribution of X-ray point sources, the cold interstellar medium, and the pattern of the dust linear polarisation in the Heiles Cloud 1 and Heiles Cloud 2 (see [8]). Heiles Cloud 1 is better known as LDN 1251 [9]. It is an elongated molecular cloud at the boundary of the Cepheus Flare giant molecular cloud (see [10, 11]). It contains dense cores (see e.g. [12]) and a num- ber of young stellar objects (see e.g. [13, 14]) with two of those, IRAS22343+7501 and IRAS22376+7455, showing water maser emission (see [15] and [16], re- spectively). The cloud is elongated, which could be the result of a low-velocity shock encounter according to [17], while [18] also investigated processes related to the magnetic field. The distance of LDN 1251 is around 340–350 pc [19–21]. Heiles Cloud 2 (HCL 2) is a large cloud in the Taurus Molecular Cloud complex. HCL 2 is sometimes referred to as TMC-1, although the TMC-1 ridge is only part of it (see e.g. [22]). HCL 2 is active in star formation with all phases present: starless cores (see e.g. [22]) protostars (see e.g. [23, 24]) and more evolved YSOs (see e.g. [22]). We will focus on the 119 https://doi.org/10.14311/AP.2025.65.0119 https://creativecommons.org/licenses/by/4.0/ https://www.cvut.cz/en N. Varga, A. P. Joo, B. Koncz Acta Polytechnica TMC-1 in our study. The distance of HCL 2 is around 140 pc [21]. Recently, [25] compared the pattern of polarisation seen in images created from Planck polarisation data to that of the distribution of a cold ISM. LDN1251 and HCL-2 showed quite different relations. 2. Data and methods 2.1. Heiles Cloud 2 To examine the structure of the HCL 2, we use the infrared data from the Herschel SPIRE at 500 µm cen- tered on RA(J2000) =4 h 41 m Dec(J2000) = 25°46′. We can see, in Figure 1, where the molecular cloud is shown in the galactic coordinate system, that the molecular cloud has a ring-like structure and it iden- tifies as the most massive molecular cloud complex in the Taurus region. HCL 2 is divided into four main clouds: (1.) TMC-1, (2.) HCL2-A, (3.) HCL2-B, and (4.) HCL2-E, HCL2-ES. The research primarily focused on the narrow, frag- mented ridge located in the eastern part of the HCL 2, referred to as Taurus Molecular Cloud 1 (TMC-1) [22]. 2.2. Taurus Molecular Cloud 1 (TMC1) Because of X-ray data availability, we focused on the TMC1 part of the HCL 2 and examined the distri- bution of X-ray point sources from the XMM-OM Serendipitous Source Survey Catalog X-ray data [26]. To further confirm and to find additional X-ray ob- servations, we add XMM-Newton Extended Survey of Taurus Molecular Cloud [27]. For the position of YSOs, we used Gaia DR3 data because it contains sources with reliable astrometry and analysis of their proper motions. Then, we cross-correlated these with a YSO sample by Gábor Marton (in prep.). 2.3. Matching sources in HCL 2 After cross-matching the X-ray data and the loca- tion of YSOs, we found three matching sources (see Figure 2). The observation of YSOs is not straight- forward, since they show a wide range of physical properties. The evolution of YSOs in the first few million years, after they emerge from their protostellar dusty envelopes, is characterised by the presence of circumstellar disks. For the classification of the YSOs, we examine their spectral energy distribution (SED), because as a YSO ages, its circumstellar environment changes, and this change is reflected in the shape of its SED. For the determination of the state of the star formation, we look at the infrared excess that comes from the dust in the ISM surrounding the object and is superimposed on the YSO’s black body radiation. Class I objects are protostars that accrete material on their forming discs and have regular outflows at Figure 1. The four main clouds in the HCL 2 on the Herschel 500 µm infrared image. their poles. Class II objects are still embedded but with a thinner disc with less infrared excess. Class III objects are pre-main sequence stars with only a faint disk. In Figure 2, we can see the three matching sources in the HCL 2. We examined their classification based on their SED and found that: (1.) is Haro 6-33 (see Figure 3), a T Tauri star at the TMC-1C. It is a class I object, where we observe a rising spectrum up to around 3 µm, followed by a flat spectrum between 3 and 22 µm caused by the presence of a substantial, infalling, circumstellar envelope [28]. (2.) is JH 223 TT* (see Figure 4), a class II YSO at TMC-1. Its SED is characterised by a decreasing flux in the 3–22 µm wavelength range. For this type of object, the emission comes only from an optically thick circumstellar disk [28]. (3.) is XEST 07-024 (see Figure 5), a class III YSO in the TMR Hole, with only a small infrared excess. The spectral energy distributions in Figures 3, 4, and 5 are derived from the photometric data taken from VizieR. The different colours indicate different sources for the data, as detailed in the appendix Ta- ble 3. The error bars represent the uncertainties of the respective measurements. Since the data points are collected from different surveys (as indicated by the colours), the presence and magnitude of the error bars depend on the original data sources. 2.4. Heiles Cloud 1 The cometary-shaped LDN 1251 is one of the promi- nent molecular clouds of the Cepheus region. We study the cloud in the 500-µm infrared with Herschel. For the position of YSOs, we use cross-correlated Gaia DR3 data with a YSO sample by Gabor Marton (in prep.). For the X-ray data, we use the XMM-Newton Serendipitous Source Catalogue 4XMM-DR13 [29] and MORX (Millions of Optical-Radio/X-ray Asso- ciations) catalogue [30], which contains the LASS, LoTSS, RACS, FIRST, NVSS, and SUMSS radio sur- 120 vol. 65 no. 1/2025 A study of X-ray point sources in Heiles Clouds 1 and 2 Figure 2. Herschel 500 µm image of the Heiles Cloud 2 with the TMC-1 ridge in the centre, the TMR Hole below it, and the TMC-1C in the upper right corner. We overlayed X-ray point sources (blue triangles) and YSOs (yellow circles), and marked the positions of three selected YSOs (see text). Figure 3. SED of Haro 6-33, a class I YSO in HCL 2. Description of the data points in Table 3. Figure 4. SED of JH 223, a class II YSO in HCL 2. Description of the data points in Table 4. Figure 5. SED of XEST 07-024, a class III YSO in HCL 2. Description of the data points in Table 5. veys, and Chandra, XMM-Newton, Swift, and ROSAT X-ray surveys. 2.5. Hardness ratio The hardness of X-ray point sources can be deter- mined by calculating the hardness ratio and it is used to show spectral properties. The purpose of investi- gating the X-ray point sources is to draw conclusion of YSO candidates using the hardness ratio (see in Hardness ratio) of each X-ray source. With the help of this index, we can compare the position of the YSO candidates and the YSOs from the Gaia DR3. Some spectral information on faint sources can be derived from the X-ray hardness ratio, defined as: HR = H − S H + S where S and H are the number of counts in the soft and hard bands, respectively. The HR values 121 N. Varga, A. P. Joo, B. Koncz Acta Polytechnica RA (J2000) DE (J2000) HR 04 40 39.13 +25 40 04.3 −0.206 04 40 49.54 +25 51 20.0 −0.811 04 40 47.15 +25 47 31.6 0.043 04 41 04.32 +25 57 55.5 −0.837 04 41 24.70 +25 54 48.4 −0.306 04 41 25.91 +25 43 47.7 −0.203 04 41 29.67 +25 38 14.5 −0.264 04 41 58.91 +25 57 50.4 −0.389 04 42 11.83 +25 31 27.3 −0.334 04 41 36.12 +25 49 59.5 0.005 04 41 38.80 +25 56 27.4 −0.105 04 40 37.41 +25 37 41.1 −0.137 04 42 28.97 +25 34 09.7 −0.18 04 40 39.75 +25 43 01.7 0.094 04 41 27.12 +25 38 04.8 −0.063 04 41 37.83 +25 55 35.9 −0.074 04 41 40.42 +25 54 12.9 0.081 04 42 04.45 +25 38 45.8 −0.06 04 42 07.41 +25 29 29.6 −0.012 04 42 08.51 +25 45 19.5 0.086 04 41 38.95 +25 24 26.5 −0.022 04 41 07.33 +25 33 41.5 0.071 04 42 08.51 +25 45 19.5 0.057 Table 1. The coordinates and hardness ratio of YSO candidates found in HCL 2. can be compared to that of the YSO in the EDR in order to select new YSO candidates. Negative values indicate a soft spectrum and positive values indicate a hard spectrum [31]. After applying this formula to the X-ray sources and determining the hardness ratio, we used the 0.5–1.0 keV and 1.0–2.0 keV bands. To define the YSO candidates, we followed the criteria from a previous publication [32], considering sources with hardness ratio values in the range of −1.0 to 0.1 as potential YSOs. As a result, we identified 20 YSO candidates in HCL 2, as shown in Table 1. The HR values for the three matching sources are as follows: Haro 6-33 has an HR value of −0.105, JH 223 has −0.811, and XEST 07-024 has 0.071. Table 2 shows the 30 YSO candidates in LDN 1251 based on their HR values. We used the XMM-Newton survey HR data [33] for the point sources we examined. 3. Results We cross-matched the X-ray sources with YSOs in TMC-1 and LDN 1251, and investigated which of the X-ray sources could be YSO candidates to compare them with known YSOs from Gaia. However, the YSO candidates identified in these two clouds do not necessarily correspond to the matched sources, indi- cating that some potential young stellar objects may not yet be confirmed or classified as known YSOs. In TMC-1, we identified 63 X-ray point sources, three of which matched known YSOs. As shown in Fig- ure 2, the distribution of X-ray sources (blue rhombs) and YSOs (yellow circles) reveals that they tend to be located around, rather than within, the densest parts of the cloud. This suggests that while ongoing star formation occurs in the densest regions, aligned RA (J2000) DE (J2000) HR 342.957757 +75.096472 −0.653135 339.666273 +75.238812 −0.628847 343.785354 +75.004985 −0.585712 343.140114 +75.217713 −0.530832 339.781313 +75.175109 −0.529483 343.137091 +75.229216 −0.523715 339.443125 +75.143217 −0.513268 339.031998 +75.359255 −0.464459 338.657758 +75.192675 −0.431929 342.488747 +75.104120 −0.426178 343.166193 +75.071182 −0.384939 343.451572 +75.106704 −0.378140 343.590204 +74.965667 −0.314152 343.285043 +75.053685 −0.309921 342.738687 +75.108034 −0.303983 339.645200 +75.200929 −0.288714 342.420129 +75.025788 −0.283266 339.677343 +75.196029 −0.280326 342.525642 +75.128734 −0.262991 339.619931 +75.249014 −0.248900 343.009320 +75.164331 −0.227124 343.285296 +75.039826 −0.216046 339.050367 +75.212686 −0.194606 343.793039 +74.954663 −0.192297 339.829930 +75.197401 −0.165193 342.484131 +75.043194 −0.160678 339.887683 +75.221501 −0.130436 342.473185 +75.120343 −0.126321 342.430687 +75.190120 −0.100328 342.560594 +74.920663 −0.097193 339.863918 +75.174516 −0.094893 339.400663 +75.097643 −0.073893 343.317712 +75.071321 −0.060079 339.550711 +75.204772 −0.025209 339.594040 +75.192727 −0.011237 339.867444 +75.399739 0.024469 339.811320 +75.121159 0.046853 343.104486 +74.890597 0.083169 340.096978 +75.204793 0.085564 343.956811 +75.123575 0.088863 338.674788 +75.238829 0.093959 343.236888 +75.158129 0.129253 343.058150 +75.055343 0.144405 339.022812 +75.308814 0.227217 342.475152 +75.167733 0.238902 343.408966 +75.289887 0.240431 343.165062 +75.105772 0.262984 339.434881 +75.223244 0.265742 339.965553 +75.326335 0.272838 338.640705 +75.286671 0.284856 343.721962 +75.128206 0.287354 343.679722 +75.045595 0.312120 342.592285 +75.157863 0.314148 339.578423 +75.198197 0.339752 339.365938 +75.257064 0.344141 339.439293 +75.346271 0.359463 338.819306 +75.313116 0.372662 338.858168 +75.175652 0.380989 342.778512 +75.130965 0.413904 339.929106 +75.240813 0.417928 342.630871 +75.095338 0.421081 343.247715 +75.163632 0.432724 340.226454 +75.156715 0.437377 339.917555 +75.222679 0.437697 339.725959 +75.321172 0.439713 343.775427 +75.201870 0.451005 343.527466 +75.078175 0.477650 342.293686 +75.011957 0.485013 339.375895 +75.134971 0.496110 343.924093 +75.162493 0.503376 Table 2. The coordinates and hardness ratios of YSO candidates found in LDN 1251. 122 vol. 65 no. 1/2025 A study of X-ray point sources in Heiles Clouds 1 and 2 Figure 6. Herschel 500-µm image of LDN 1251 with the X-ray sources (blue triangles) and YSOs (yellow circles). with the structure of the cloud, young stars and X-ray sources become more detectable as they emerge from their birth sites, where extinction is lower. Similarly, in LDN 1251, we found 64 X-ray point sources, 20 of which matched known YSOs. Figure 6 illustrates that both X-ray sources and YSOs are posi- tioned around the cloud rather than deeply embedded in the most opaque regions. This spatial distribution is consistent with the expectation that young stellar objects, especially those in later evolutionary stages, become more visible in X-rays once they have cleared away some of their surrounding material. Addition- ally, the correlation between the X-ray sources and the YSOs outside the densest areas may indicate regions of recent or ongoing star formation, where emerging stars become X-ray active as they evolve. 3.1. Polarisation The phenomenon of polarisation was described as early as the 1950s [34], and since then, it has remained one of the most important methods for studying the struc- ture of magnetic fields. Magnetic fields play a crucial role in star formation processes at all scales. A precise and detailed determination of their properties – includ- ing strength and spatial orientation – is essential for a thorough understanding of the physical characteris- tics of molecular clouds, star cores, and protoplanetary disks. For the investigation of the magnetic field as- sociated with star-forming regions, we examined the polarised dust emission. This method, which involves studying polarised emission in the far-infrared and millimeter wavelength ranges, is one of the most suit- able techniques for exploring the magnetic field of molecular clouds [35]. Using Planck’s all-sky intensity and polarisation maps at 353 GHz, we extracted the regions HCL 1 and HCL 2 and calculated the magnetic field orien- tation. We used a Line Integral Convolution (LIC) method to visualise the field lines and blended these with the intensity maps, imprinting the field structure Figure 7. Magnetic field orientation and relative strength perpendicular to the line of sight in LDN 1251 based on Planck polarimetry data. The field struc- ture is visualised using an LIC method blended with intensity, with an overlaid vector field representation indicating the relative field strength perpendicular to the line of sight. as darker lines. This allowed us to observe the rela- tionship between the intensity and the magnetic field orientation. In Figures 7 and 8, we also overlaid a vector repre- sentation of the magnetic field onto the LIC composite to observe the relative field strength in different areas of LDN 1251 and HCL 2. The vectors’ length shows the intensity of the magnetic field’s transverse com- ponent to the line of sight. Because of this, a shorter vector can also mean a rotation of the magnetic field. Figures 9 and 10 show YSOs as white plus (+) and X-ray point sources as yellow cross (×) symbols, over- laid on the LIC composite of the intensity and mag- netic field. The majority of the YSOs are concentrated in the dense part of the clouds. 123 N. Varga, A. P. Joo, B. Koncz Acta Polytechnica Figure 8. Magnetic field orientation and relative strength perpendicular to the line of sight in HCL 2 based on Planck polarimetry data. The field struc- ture is visualised using an LIC method blended with intensity, with an overlaid vector field representation indicating the relative field strength perpendicular to the line of sight. Figure 9. Magnetic field orientation in LDN 1251 based on Planck polarimetry data, with overlaid YSOs as plus (+) and X-ray point sources as cross (×) sym- bols. The field structure is visualised using an LIC method blended with intensity. 3.2. Comparison The vectors indicate the direction of the magnetic field. Both cloud’s magnetic field vectors are aligned, suggesting a more ordered magnetic field. But we could not make any assumptions about the structure of the magnetic field, for that we need a higher resolution. In the future, we plan to conduct a correlation analysis to examine the relationship between the magnetic field properties and other characteristics of the clouds. A more detailed and in-depth investigation of the magnetic field will be carried out later, including comparative studies to better understand its role in the cloud dynamics. Figure 10. Magnetic field orientation in HCL 2 based on Planck polarimetry data, with overlaid YSOs marked as plus (+) and X-ray point sources as cross (×) symbols. The field structure is visualised using an LIC method blended with intensity. Acknowledgements The IBWS conference participation of B. Koncz was sub- sidized by the Dean’s Council of ELTE Eötvös Loránd University Faculty of Science, Budapest. This research has made use of the SIMBAD database, operated at CDS, Strasbourg, France [36]. This research has made use of Aladin sky atlas developed at CDS, Strasbourg Observatory, France [37]. This research has made use of the VizieR catalogue access tool, CDS, Strasbourg, France. The original de- scription of the VizieR service was published in [38]. We are grateful to L. 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Astronomy and Astrophysics Supplement Series 143(1):23–32, 2000. https://doi.org/10.1051/aas:2000169 126 https://doi.org/10.1086/317728 https://doi.org/10.1051/aas:2000332 https://doi.org/10.1051/aas:2000331 https://doi.org/10.1051/aas:2000169 vol. 65 no. 1/2025 A study of X-ray point sources in Heiles Clouds 1 and 2 Appendix A. Table 3. Data points on Figure 3 for Haro 6-33 from VizieR Photometry viewer. λ νF(ν) Error Vizier table Vizier ID[µm] [Wm−2] [Wm−2] 0.34 6.88 × 10−17 5.40 × 10−18 II/370/xmmom5s recno=1493997 0.34 6.89 × 10−17 5.40 × 10−18 II/356/xmmom41s recno=1404730 0.35 1.35 × 10−16 9.37 × 10−18 J/ApJS/253/19/mstars recno=45351 0.35 1.37 × 10−16 9.37 × 10−18 IV/34/epic ID=248018164&-c=070.411763 +25.940765,eq=J2000&-c.rs=0.004 0.35 1.41 × 10−16 1.02 × 10−17 V/154/sdss16 -c=070.411754 +25.940758,eq=ICRS&-c.rs=0.004 0.35 1.43 × 10−16 1.02 × 10−17 I/353/gsc242 -c=070.41180397042 +25.94067833689,eq=ICRS&- c.rs=0.004 0.44 6.36 × 10−16 9.58 × 10−17 IV/38/tic -c=070.41179395162 +25.94078969880,eq=J2000&- c.rs=0.004 0.44 1.05 × 10−15 4.39 × 10−16 I/305/out GSC2.3===N9RV004914&-c=070.411814 +25.940912,eq=J2000&-c.rs=0.00 0.47 8.33 × 10−16 3.14 × 10−16 I/305/out GSC2.3===N9RV004914&-c=070.411814 +25.940912,eq=J2000&-c.rs=0.00 0.48 1.12 × 10−15 3.14 × 10−17 II/349/ps1 -c=070.411801850 +25.940684730,eq=J2000&- c.rs=0.004 0.48 1.37 × 10−15 3.14 × 10−17 J/AJ/156/241/table4 recno=2882736 0.48 6.47 × 10−16 6.22 × 10−18 IV/34/epic ID=248018164&-c=070.411763 +25.940765,eq=J2000&-c.rs=0.004 0.48 1.11 × 10−15 3.11 × 10−17 I/353/gsc242 -c=070.41180397042 +25.94067833689,eq=ICRS&- c.rs=0.004 0.50 2.10 × 10−15 1.19 × 10−16 I/350/gaiaedr3 -c=070.41180463045 +25.94067562056,eq=ICRS&- c.rs=0.004 0.50 2.00 × 10−15 1.90 × 10−16 I/345/gaia2 -c=070.41180397042 +25.94067833689,eq=ICRS&- c.rs=0.004 0.55 8.61 × 10−16 J/MNRAS/444/1157/table2 recno=133 0.55 2.67 × 10−15 II/366/catv2021 recno=518426 0.58 6.80 × 10−15 1.54 × 10−16 I/350/gaiaedr3 -c=070.41180463045 +25.94067562056,eq=ICRS&- c.rs=0.004 0.61 4.82 × 10−15 2.50 × 10−16 II/349/ps1 -c=070.411801850 +25.940684730,eq=J2000&- c.rs=0.004 0.61 4.94 × 10−15 0 × 10+0 J/AJ/156/241/table4 recno=2882736 0.62 6.69 × 10−15 1.44 × 10−16 I/345/gaia2 -c=070.41180397042 +25.94067833689,eq=ICRS&- c.rs=0.004 0.62 3.48 × 10−15 1.44 × 10−17 V/154/sdss16 -c=070.411754 +25.940758,eq=ICRS&-c.rs=0.004 0.62 3.49 × 10−15 1.44 × 10−17 J/ApJS/253/19/mstars recno=45351 0.62 3.50 × 10−15 1.44 × 10−17 V/154/sdss16 -c=070.411761 +25.940764,eq=ICRS&-c.rs=0.004 0.62 3.50 × 10−15 1.44 × 10−17 IV/34/epic ID=248018164&-c=070.411763 +25.940765,eq=J2000&-c.rs=0.004 0.62 4.74 × 10−15 2.45 × 10−16 I/353/gsc242 -c=070.41180397042 +25.94067833689,eq=ICRS&- c.rs=0.004 0.64 5.81 × 10−15 2.20 × 10−15 I/305/out GSC2.3===N9RV004914&-c=070.411814 +25.940912,eq=J2000&-c.rs=0.00 0.67 1.28 × 10−15 1.11 × 10−16 I/353/gsc242 -c=070.41180397042 +25.94067833689,eq=ICRS&- c.rs=0.004 0.67 5.48 × 10−15 J/AJ/162/110/table1 recno=432 0.67 5.52 × 10−15 1.34 × 10−16 II/366/catv2021 recno=518426 0.67 5.66 × 10−15 1.34 × 10−16 I/353/gsc242 -c=070.41180397042 +25.94067833689,eq=ICRS&- c.rs=0.004 0.67 9.98 × 10−15 I/337/gaia -c=070.4118028781 +25.9406807597,eq=ICRS&- c.rs=0.004 0.67 2.33 × 10−14 1.60 × 10−15 I/353/gsc242 -c=070.41180397042 +25.94067833689,eq=ICRS&- c.rs=0.004 0.75 1.06 × 10−14 1.60 × 10−16 J/AJ/156/241/table4 recno=2882736 0.75 1.34 × 10−14 3.21 × 10−16 II/349/ps1 -c=070.411801850 +25.940684730,eq=J2000&- c.rs=0.004 0.76 1.90 × 10−14 1.14 × 10−15 I/350/gaiaedr3 -c=070.41180463045 +25.94067562056,eq=ICRS&- c.rs=0.004 0.76 1.03 × 10−14 3.93 × 10−17 V/154/sdss16 -c=070.411754 +25.940758,eq=ICRS&-c.rs=0.004 0.76 1.04 × 10−14 3.93 × 10−17 V/154/sdss16 -c=070.411761 +25.940764,eq=ICRS&-c.rs=0.004 0.76 1.04 × 10−14 3.93 × 10−17 J/ApJS/253/19/mstars recno=45351 0.76 1.04 × 10−14 3.93 × 10−17 IV/34/epic ID=248018164&-c=070.411763 +25.940765,eq=J2000&-c.rs=0.004 0.76 1.32 × 10−14 3.14 × 10−16 I/353/gsc242 -c=070.41180397042 +25.94067833689,eq=ICRS&- c.rs=0.004 127 N. Varga, A. P. Joo, B. Koncz Acta Polytechnica λ νF(ν) Error Vizier table Vizier ID[µm] [Wm−2] [Wm−2] 0.77 1.77 × 10−14 1.32 × 10−15 I/345/gaia2 -c=070.41180397042 +25.94067833689,eq=ICRS&- c.rs=0.004 0.78 1.34 × 10−14 5.28 × 10−15 I/305/out GSC2.3===N9RV004914&-c=070.411814 +25.940912,eq=J2000&-c.rs=0.00 0.79 5.66 × 10−15 J/MNRAS/444/1157/table2 recno=133 0.87 1.85 × 10−14 1.14 × 10−15 J/AJ/156/241/table4 recno=2882736 0.87 2.62 × 10−14 4.85 × 10−16 II/349/ps1 -c=070.411801850 +25.940684730,eq=J2000&- c.rs=0.004 0.88 3.37 × 10−14 3.40 × 10−17 II/319/gcs9 -c=070.411794 +25.940742,eq=J2000&-c.rs=0.004 0.90 2.51 × 10−14 4.65 × 10−16 I/353/gsc242 -c=070.41180397042 +25.94067833689,eq=ICRS&- c.rs=0.004 0.90 2.59 × 10−14 9.97 × 10−17 V/154/sdss16 -c=070.411754 +25.940758,eq=ICRS&-c.rs=0.004 0.90 2.59 × 10−14 9.97 × 10−17 V/154/sdss16 -c=070.411761 +25.940764,eq=ICRS&-c.rs=0.004 0.90 2.62 × 10−14 9.97 × 10−17 IV/34/epic ID=248018164&-c=070.411763 +25.940765,eq=J2000&-c.rs=0.004 0.96 3.28 × 10−14 9.37 × 10−16 J/AJ/156/241/table4 recno=2882736 0.96 4.69 × 10−14 2.19 × 10−15 II/349/ps1 -c=070.411801850 +25.940684730,eq=J2000&- c.rs=0.004 1.03 6.55 × 10−14 0 × 10+0 II/319/gcs9 -c=070.411794 +25.940742,eq=J2000&-c.rs=0.004 1.24 6.94 × 10−14 I/297/out NOMAD1===1159-0059642&-c=070.4117639 +25.9409889,eq=J2000&-c.rs= 1.24 7.02 × 10−14 1.45 × 10−15 II/332/c2d recno=5309093 1.25 1.13 × 10−13 0 × 10+0 II/319/gcs9 -c=070.411794 +25.940742,eq=J2000&-c.rs=0.004 1.25 7.03 × 10−14 1.44 × 10−15 II/246/out 2MASS===04413882+2556267 &-c=070.411763 +25.940765,eq=J2000&-c.r 1.25 7.15 × 10−14 7.19 × 10−16 II/246/out 2MASS===04413882+2556267 &-c=070.411763 +25.940765,eq=J2000&-c.r 1.63 1.71 × 10−13 3.49 × 10−15 II/246/out 2MASS===04413882+2556267 &-c=070.411763 +25.940765,eq=J2000&-c.r 1.63 1.73 × 10−13 9.20 × 10−16 II/246/out 2MASS===04413882+2556267 &-c=070.411763 +25.940765,eq=J2000&-c.r 1.65 1.63 × 10−13 3.27 × 10−15 II/368/sstsl2 -c=070.4117764 +25.9407545,eq=J2000&- c.rs=0.004 1.65 1.65 × 10−13 3.45 × 10−15 II/332/c2d recno=5309093 1.65 1.66 × 10−13 II/338/catalog recno=38622 1.65 1.70 × 10−13 3.45 × 10−15 I/317/sample PPMXL=3103192842720665194&-c=070.411801 +25.940901,eq=J2000&-c.r 1.65 1.70 × 10−13 I/297/out NOMAD1===1159-0059642&-c=070.4117639 +25.9409889,eq=J2000&-c.rs= 2.16 1.90 × 10−13 2.77 × 10−15 II/368/sstsl2 -c=070.4117764 +25.9407545,eq=J2000&- c.rs=0.004 2.16 1.93 × 10−13 2.77 × 10−15 II/332/c2d recno=5309093 2.16 1.95 × 10−13 2.77 × 10−15 I/317/sample PPMXL=3103192842720665194&-c=070.411801 +25.940901,eq=J2000&-c.r 2.19 1.86 × 10−13 2.74 × 10−15 II/246/out 2MASS===04413882+2556267 &-c=070.411763 +25.940765,eq=J2000&-c.r 2.19 1.89 × 10−13 1.37 × 10−15 II/246/out 2MASS===04413882+2556267 &-c=070.411763 +25.940765,eq=J2000&-c.r 2.20 5.45 × 10−14 0 × 10+0 II/316/gps6 -c=070.411786 +25.940733,eq=ICRS&-c.rs=0.004 2.20 9.40 × 10−14 II/319/gcs9 -c=070.411794 +25.940742,eq=J2000&-c.rs=0.004 2.20 1.59 × 10−13 II/316/gps6 -c=070.411786 +25.940733,eq=ICRS&-c.rs=0.004 2.20 2.08 × 10−13 II/316/gps6 -c=070.411786 +25.940733,eq=ICRS&-c.rs=0.004 3.35 1.40 × 10−13 2.68 × 10−15 II/365/catwise -c=070.4118218 +25.9406836,eq=ICRS&- c.rs=0.004 3.35 1.45 × 10−13 2.68 × 10−15 II/368/sstsl2 -c=070.4117764 +25.9407545,eq=J2000&- c.rs=0.004 3.35 1.47 × 10−13 2.68 × 10−15 I/353/gsc242 -c=070.41180397042 +25.94067833689,eq=ICRS&- c.rs=0.004 3.35 1.49 × 10−13 0 × 10+0 II/363/unwise -c=070.4118104 +25.9407152,eq=J2000&- c.rs=0.004 3.35 1.50 × 10−13 II/338/catalog recno=38622 3.35 1.51 × 10−13 3.58 × 10−15 II/311/wise WISE===J044138.82+255626.7&-c=070.411789 +25.940759,eq=J2000&-c. 3.55 9.80 × 10−14 6.76 × 10−15 II/332/c2d recno=5309093 3.55 1.20 × 10−13 5.91 × 10−15 J/ApJS/186/259/known recno=206 3.55 1.25 × 10−13 2.53 × 10−15 J/ApJ/784/126/table1 recno=346 4.49 9.61 × 10−14 4.67 × 10−15 J/ApJS/186/259/known recno=206 4.49 1.06 × 10−13 6.01 × 10−15 II/332/c2d recno=5309093 4.49 1.08 × 10−13 2.00 × 10−15 J/ApJ/784/126/table1 recno=346 4.60 1.15 × 10−13 1.30 × 10−15 II/365/catwise -c=070.4118218 +25.9406836,eq=ICRS&- c.rs=0.004 128 vol. 65 no. 1/2025 A study of X-ray point sources in Heiles Clouds 1 and 2 λ νF(ν) Error Vizier table Vizier ID[µm] [Wm−2] [Wm−2] 4.60 1.19 × 10−13 0 × 10+0 II/363/unwise -c=070.4118104 +25.9407152,eq=J2000&- c.rs=0.004 4.60 1.23 × 10−13 1.96 × 10−15 II/368/sstsl2 -c=070.4117764 +25.9407545,eq=J2000&- c.rs=0.004 4.60 1.25 × 10−13 1.96 × 10−15 I/353/gsc242 -c=070.41180397042 +25.94067833689,eq=ICRS&- c.rs=0.004 4.60 1.27 × 10−13 1.96 × 10−15 II/311/wise WISE===J044138.82+255626.7&-c=070.411789 +25.940759,eq=J2000&-c. 4.60 1.28 × 10−13 2.61 × 10−15 J/ApJ/784/126/table1 recno=346 4.60 1.28 × 10−13 II/338/catalog recno=38622 5.73 8.47 × 10−14 3.66 × 10−15 J/ApJS/186/259/known recno=206 5.73 9.73 × 10−14 2.62 × 10−15 J/ApJ/784/126/table1 recno=346 5.73 1.06 × 10−13 0 × 10+0 II/368/sstsl2 -c=070.4117764 +25.9407545,eq=J2000&- c.rs=0.004 5.73 1.30 × 10−13 6.28 × 10−15 II/332/c2d recno=5309093 7.87 9.29 × 10−14 4.19 × 10−15 J/ApJS/186/259/known recno=206 7.87 1.01 × 10−13 2.67 × 10−15 J/ApJ/784/126/table1 recno=346 7.87 1.07 × 10−13 0 × 10+0 II/368/sstsl2 -c=070.4117764 +25.9407545,eq=J2000&- c.rs=0.004 7.87 1.61 × 10−13 9.90 × 10−15 II/332/c2d recno=5309093 8.61 1.25 × 10−13 4.87 × 10−15 II/338/catalog recno=38622 11.56 1.11 × 10−13 1.04 × 10−15 J/AJ/158/54/table1 recno=414 11.56 1.11 × 10−13 1.30 × 10−15 II/328/allwise AllWISE===J044138.83+255626.6&- c=070.4117932 +25.9407276,eq=J200 11.56 1.11 × 10−13 1.30 × 10−15 I/353/gsc242 -c=070.41180397042 +25.94067833689,eq=ICRS&- c.rs=0.004 11.56 1.12 × 10−13 1.04 × 10−15 J/ApJ/784/126/table1 recno=346 11.56 1.12 × 10−13 1.30 × 10−15 II/311/wise WISE===J044138.82+255626.7&-c=070.411789 +25.940759,eq=J2000&-c. 11.56 1.19 × 10−13 1.30 × 10−15 II/368/sstsl2 -c=070.4117764 +25.9407545,eq=J2000&- c.rs=0.004 11.56 1.23 × 10−13 II/338/catalog recno=38622 11.59 1.40 × 10−13 II/338/catalog recno=38622 11.59 1.48 × 10−13 II/338/catalog recno=38622 18.39 1.56 × 10−13 5.22 × 10−15 II/338/catalog recno=38622 22.09 1.72 × 10−13 2.71 × 10−15 II/368/sstsl2 -c=070.4117764 +25.9407545,eq=J2000&- c.rs=0.004 22.09 1.75 × 10−13 2.71 × 10−15 I/353/gsc242 -c=070.41180397042 +25.94067833689,eq=ICRS&- c.rs=0.004 22.09 1.76 × 10−13 1.36 × 10−15 J/ApJ/784/126/table1 recno=346 22.09 1.78 × 10−13 2.71 × 10−15 II/311/wise WISE===J044138.82+255626.7&-c=070.411789 +25.940759,eq=J2000&-c. 22.09 1.79 × 10−13 II/338/catalog recno=38622 23.67 1.61 × 10−13 1.52 × 10−14 II/332/c2d recno=5309093 23.67 1.63 × 10−13 6.33 × 10−15 J/ApJ/784/126/table1 recno=346 23.67 1.67 × 10−13 0 × 10+0 II/368/sstsl2 -c=070.4117764 +25.9407545,eq=J2000&- c.rs=0.004 23.67 6.46 × 10−12 2.41 × 10−13 J/ApJ/836/34/table2 recno=780 23.88 1.91 × 10−13 II/338/catalog recno=38622 23.88 1.95 × 10−13 II/338/catalog recno=38622 61.85 1.33 × 10−13 II/338/catalog recno=38622 61.85 1.40 × 10−13 II/338/catalog recno=38622 70.00 1.23 × 10−13 2.14 × 10−15 J/A+A/688/A203/bshrcds recno=5342 70.00 1.24 × 10−13 2.57 × 10−14 J/ApJ/849/63/ysos recno=109 71.42 7.47 × 10−14 1.51 × 10−14 J/ApJS/186/259/known recno=206 71.42 8.86 × 10−14 8.40 × 10−15 II/332/c2d recno=5309093 100.00 8.99 × 10−14 1.80 × 10−14 J/ApJ/849/63/ysos recno=109 101.95 1.71 × 10−13 II/338/catalog recno=38622 101.95 2.36 × 10−13 II/338/catalog recno=38622 155.90 3.79 × 10−14 7.69 × 10−15 J/ApJS/186/259/known recno=206 160.00 4.87 × 10−14 9.37 × 10−15 J/ApJ/849/63/ysos recno=109 249.99 1.56 × 10−14 3.60 × 10−15 J/ApJ/849/63/ysos recno=109 249.99 1.73 × 10−14 3.60 × 10−16 VIII/112/spsc250 recno=263696 249.99 1.75 × 10−14 2.40 × 10−16 VIII/112/spsc250 recno=263696 249.99 1.93 × 10−14 2.40 × 10−16 VIII/112/spsc250 recno=263696 249.99 1.95 × 10−14 3.60 × 10−16 VIII/112/spsc250 recno=263696 363.00 5.78 × 10−15 8.26 × 10−16 J/ApJ/849/63/ysos recno=109 886.96 2.00 × 10−16 2.84 × 10−17 J/ApJ/771/129/table2 recno=171 1300.00 5.88 × 10−17 5.07 × 10−18 J/ApJ/872/158/table4 recno=176 1332.41 5.74 × 10−17 4.95 × 10−18 J/ApJ/771/129/table2 recno=171 129 N. Varga, A. P. Joo, B. Koncz Acta Polytechnica Table 4. Data points on Figure 4 for JH 223 from VizieR Photometry viewer. λ νF(ν) Error Vizier table Vizier ID[µm] [Wm−2] [Wm−2] 0.34 6.83 × 10−16 1.13 × 10−17 II/370/xmmom5s recno=1493547 0.34 6.84 × 10−16 1.13 × 10−17 II/356/xmmom41s recno=1404279 0.35 8.49 × 10−16 1.62 × 10−17 V/154/sdss16 -c=070.206253 +25.855252,eq=ICRS&-c.rs=0.004 0.35 8.60 × 10−16 1.70 × 10−17 I/353/gsc242 -c=070.20631586592 +25.85518403387,eq=ICRS&- c.rs=0.004 0.35 8.69 × 10−16 1.70 × 10−17 IV/38/tic -c=070.20629490024 +25.85526855322,eq=J2000&- c.rs=0.004 0.35 9.80 × 10−16 1.70 × 10−17 V/154/sdss16 -c=070.206253 +25.855252,eq=ICRS&-c.rs=0.004 0.35 9.88 × 10−16 1.70 × 10−17 V/154/sdss16 -c=070.206247 +25.855259,eq=ICRS&-c.rs=0.004 0.40 2.08 × 10−13 I/358/varisum -c= 70.20631650736 +25.85518131742,eq=ICRS&- c.rs=0.004 0.44 2.96 × 10−15 1.23 × 10−15 I/305/out GSC2.3===N9RV000756&-c=070.206325 +25.855384,eq=J2000&-c.rs=0.00 0.44 5.43 × 10−15 II/336/apass9 -c=070.206175 +25.855062,eq=J2000&-c.rs=0.004 0.47 6.02 × 10−15 2.33 × 10−15 I/305/out GSC2.3===N9RV000756&-c=070.206325 +25.855384,eq=J2000&-c.rs=0.00 0.48 7.10 × 10−15 J/AJ/156/241/table4 recno=2879389 0.48 7.73 × 10−15 1.26 × 10−16 II/349/ps1 -c=070.206312620 +25.855188720,eq=J2000&- c.rs=0.004 0.48 5.47 × 10−15 2.49 × 10−17 IV/38/tic -c=070.20629490024 +25.85526855322,eq=J2000&- c.rs=0.004 0.48 5.48 × 10−15 2.49 × 10−17 V/154/sdss16 -c=070.206253 +25.855252,eq=ICRS&-c.rs=0.004 0.48 6.16 × 10−15 2.49 × 10−17 V/154/sdss16 -c=070.206253 +25.855252,eq=ICRS&-c.rs=0.004 0.48 6.18 × 10−15 2.49 × 10−17 V/154/sdss16 -c=070.206247 +25.855259,eq=ICRS&-c.rs=0.004 0.48 7.21 × 10−15 5.60 × 10−16 II/336/apass9 -c=070.206175 +25.855062,eq=J2000&-c.rs=0.004 0.48 7.71 × 10−15 1.24 × 10−16 I/353/gsc242 -c=070.20631586592 +25.85518403387,eq=ICRS&- c.rs=0.004 0.50 1.08 × 10−14 2.38 × 10−16 I/350/gaiaedr3 -c=070.20631650736 +25.85518131742,eq=ICRS&- c.rs=0.004 0.50 1.04 × 10−14 2.97 × 10−16 I/345/gaia2 -c=070.20631586592 +25.85518403387,eq=ICRS&- c.rs=0.004 0.55 8.61 × 10−15 1.73 × 10−15 IV/38/tic -c=070.20629490024 +25.85526855322,eq=J2000&- c.rs=0.004 0.55 1.33 × 10−14 II/336/apass9 -c=070.206175 +25.855062,eq=J2000&-c.rs=0.004 0.58 3.82 × 10−14 2.57 × 10−16 I/350/gaiaedr3 -c=070.20631650736 +25.85518131742,eq=ICRS&- c.rs=0.004 0.61 2.38 × 10−14 J/AJ/156/241/table4 recno=2879389 0.61 2.47 × 10−14 1.47 × 10−16 II/349/ps1 -c=070.206312620 +25.855188720,eq=J2000&- c.rs=0.004 0.62 3.51 × 10−14 2.89 × 10−16 I/345/gaia2 -c=070.20631586592 +25.85518403387,eq=ICRS&- c.rs=0.004 0.62 2.22 × 10−14 9.60 × 10−17 V/154/sdss16 -c=070.206253 +25.855252,eq=ICRS&-c.rs=0.004 0.62 2.23 × 10−14 9.60 × 10−17 V/154/sdss16 -c=070.206247 +25.855259,eq=ICRS&-c.rs=0.004 0.62 2.43 × 10−14 1.44 × 10−16 I/353/gsc242 -c=070.20631586592 +25.85518403387,eq=ICRS&- c.rs=0.004 0.62 2.46 × 10−14 1.44 × 10−16 IV/38/tic -c=070.20629490024 +25.85526855322,eq=J2000&- c.rs=0.004 0.62 2.58 × 10−14 8.64 × 10−16 II/336/apass9 -c=070.206175 +25.855062,eq=J2000&-c.rs=0.004 0.64 3.07 × 10−14 1.19 × 10−14 I/305/out GSC2.3===N9RV000756&-c=070.206325 +25.855384,eq=J2000&-c.rs=0.00 0.67 2.28 × 10−15 J/AJ/166/218/table1 recno=22809 0.67 6.68 × 10−15 1.78 × 10−16 I/353/gsc242 -c=070.20631586592 +25.85518403387,eq=ICRS&- c.rs=0.004 0.67 6.82 × 10−15 J/AJ/166/218/table1 recno=22809 0.67 2.97 × 10−14 J/ApJ/917/23/table2 recno=27491 0.67 2.97 × 10−14 2.23 × 10−16 I/353/gsc242 -c=070.20631586592 +25.85518403387,eq=ICRS&- c.rs=0.004 0.67 3.08 × 10−14 J/ApJ/917/23/table1 recno=28207 0.67 3.08 × 10−14 III/286/catalog recno=108605 0.67 3.55 × 10−14 I/337/gaia -c=070.2063157402 +25.8551866093,eq=ICRS&- c.rs=0.004 0.67 9.49 × 10−14 2.23 × 10−15 I/353/gsc242 -c=070.20631586592 +25.85518403387,eq=ICRS&- c.rs=0.004 0.67 9.76 × 10−14 J/AJ/166/218/table1 recno=22809 0.75 4.21 × 10−14 J/AJ/156/241/table4 recno=2879389 0.75 5.93 × 10−14 II/349/ps1 -c=070.206312620 +25.855188720,eq=J2000&- c.rs=0.004 0.76 7.28 × 10−14 1.57 × 10−15 I/350/gaiaedr3 -c=070.20631650736 +25.85518131742,eq=ICRS&- c.rs=0.004 130 vol. 65 no. 1/2025 A study of X-ray point sources in Heiles Clouds 1 and 2 λ νF(ν) Error Vizier table Vizier ID[µm] [Wm−2] [Wm−2] 0.76 6.01 × 10−14 3.93 × 10−16 V/154/sdss16 -c=070.206253 +25.855252,eq=ICRS&-c.rs=0.004 0.76 6.05 × 10−14 3.93 × 10−16 V/154/sdss16 -c=070.206247 +25.855259,eq=ICRS&-c.rs=0.004 0.76 6.83 × 10−14 3.93 × 10−16 IV/38/tic -c=070.20629490024 +25.85526855322,eq=J2000&- c.rs=0.004 0.76 8.05 × 10−14 4.32 × 10−15 II/336/apass9 -c=070.206175 +25.855062,eq=J2000&-c.rs=0.004 0.77 7.18 × 10−14 1.94 × 10−15 I/345/gaia2 -c=070.20631586592 +25.85518403387,eq=ICRS&- c.rs=0.004 0.78 1.22 × 10−13 4.82 × 10−14 I/305/out GSC2.3===N9RV000756&-c=070.206325 +25.855384,eq=J2000&-c.rs=0.00 0.87 6.44 × 10−14 J/AJ/156/241/table4 recno=2879389 0.87 1.03 × 10−13 II/349/ps1 -c=070.206312620 +25.855188720,eq=J2000&- c.rs=0.004 0.88 1.08 × 10−13 0 × 10+0 II/319/gcs9 -c=070.206305 +25.855240,eq=J2000&-c.rs=0.004 0.90 1.12 × 10−13 3.32 × 10−16 V/154/sdss16 -c=070.206253 +25.855252,eq=ICRS&-c.rs=0.004 0.90 1.13 × 10−13 3.32 × 10−16 J/ApJS/253/19/mstars recno=334526 0.90 1.14 × 10−13 3.32 × 10−16 IV/38/tic -c=070.20629490024 +25.85526855322,eq=J2000&- c.rs=0.004 0.90 1.17 × 10−13 3.32 × 10−16 V/154/sdss16 -c=070.206247 +25.855259,eq=ICRS&-c.rs=0.004 0.90 1.19 × 10−13 3.32 × 10−16 V/154/sdss16 -c=070.206253 +25.855252,eq=ICRS&-c.rs=0.004 0.96 7.84 × 10−14 J/AJ/156/241/table4 recno=2879389 0.96 1.28 × 10−13 4.69 × 10−15 II/349/ps1 -c=070.206312620 +25.855188720,eq=J2000&- c.rs=0.004 1.03 1.17 × 10−13 0 × 10+0 II/319/gcs9 -c=070.206305 +25.855240,eq=J2000&-c.rs=0.004 1.24 1.91 × 10−13 4.11 × 10−15 II/368/sstsl2 -c=070.2062531 +25.8553357,eq=J2000&-c.rs=0.004 1.24 1.91 × 10−13 I/297/out NOMAD1===1158-0059949&-c=070.2062519 +25.8552747,eq=J2000&-c.rs= 1.24 1.93 × 10−13 4.11 × 10−15 II/332/c2d recno=5236589 1.25 1.35 × 10−13 2.40 × 10−16 II/319/gcs9 -c=070.206305 +25.855240,eq=J2000&-c.rs=0.004 1.25 1.94 × 10−13 4.08 × 10−15 II/246/out 2MASS===04404950+2551191 &-c=070.206284 +25.855328,eq=J2000&-c.r 1.25 2.06 × 10−13 2.16 × 10−15 II/246/out 2MASS===04404950+2551191 &-c=070.206284 +25.855328,eq=J2000&-c.r 1.63 2.06 × 10−13 5.52 × 10−15 II/246/out 2MASS===04404950+2551191 &-c=070.206284 +25.855328,eq=J2000&-c.r 1.63 2.17 × 10−13 3.68 × 10−15 II/246/out 2MASS===04404950+2551191 &-c=070.206284 +25.855328,eq=J2000&-c.r 1.65 1.96 × 10−13 5.45 × 10−15 II/368/sstsl2 -c=070.2062531 +25.8553357,eq=J2000&-c.rs=0.004 1.65 2.00 × 10−13 5.45 × 10−15 II/332/c2d recno=5236589 1.65 2.05 × 10−13 I/297/out NOMAD1===1158-0059949&-c=070.2062519 +25.8552747,eq=J2000&-c.rs= 2.16 1.45 × 10−13 2.77 × 10−15 II/368/sstsl2 -c=070.2062531 +25.8553357,eq=J2000&-c.rs=0.004 2.16 1.47 × 10−13 2.77 × 10−15 II/332/c2d recno=5236589 2.16 1.50 × 10−13 2.77 × 10−15 I/317/sample PPMXL=3103050302883991366&-c=070.206291 +25.855327,eq=J2000&-c.r 2.19 1.42 × 10−13 2.74 × 10−15 II/246/out 2MASS===04404950+2551191 &-c=070.206284 +25.855328,eq=J2000&-c.r 2.19 1.46 × 10−13 1.37 × 10−15 II/246/out 2MASS===04404950+2551191 &-c=070.206284 +25.855328,eq=J2000&-c.r 2.20 1.04 × 10−13 1.36 × 10−16 II/316/gps6 -c=070.206302 +25.855240,eq=ICRS&-c.rs=0.004 2.20 1.16 × 10−13 II/316/gps6 -c=070.206302 +25.855240,eq=ICRS&-c.rs=0.004 2.20 1.17 × 10−13 II/316/gps6 -c=070.206302 +25.855240,eq=ICRS&-c.rs=0.004 3.35 7.19 × 10−14 0 × 10+0 II/363/unwise -c=070.2062786 +25.8552530,eq=J2000&-c.rs=0.004 3.35 7.19 × 10−14 1.52 × 10−15 II/368/sstsl2 -c=070.2062531 +25.8553357,eq=J2000&-c.rs=0.004 3.35 7.23 × 10−14 8.05 × 10−16 II/365/catwise -c=070.2062953 +25.8552378,eq=ICRS&-c.rs=0.004 3.35 7.28 × 10−14 1.34 × 10−15 J/AJ/158/54/table1 recno=404 3.35 7.29 × 10−14 1.52 × 10−15 I/353/gsc242 -c=070.20631586592 +25.85518403387,eq=ICRS&- c.rs=0.004 3.35 7.55 × 10−14 1.43 × 10−15 J/ApJ/784/126/table1 recno=338 3.35 7.60 × 10−14 1.61 × 10−15 II/311/wise WISE===J044049.50+255119.0&-c=070.206275 +25.855304,eq=J2000&-c. 3.55 4.57 × 10−14 0 × 10+0 II/368/sstsl2 -c=070.2062531 +25.8553357,eq=J2000&-c.rs=0.004 3.55 5.65 × 10−14 4.39 × 10−15 II/332/c2d recno=5236589 3.55 6.51 × 10−14 3.04 × 10−15 J/ApJS/186/259/known recno=200 3.55 6.76 × 10−14 1.27 × 10−15 J/ApJ/784/126/table1 recno=338 4.49 3.07 × 10−14 0 × 10+0 II/368/sstsl2 -c=070.2062531 +25.8553357,eq=J2000&-c.rs=0.004 4.49 4.28 × 10−14 2.87 × 10−15 II/332/c2d recno=5236589 4.49 4.35 × 10−14 2.00 × 10−15 J/ApJS/186/259/known recno=200 4.49 4.64 × 10−14 8.67 × 10−16 J/ApJ/784/126/table1 recno=338 4.60 4.29 × 10−14 0 × 10+0 II/363/unwise -c=070.2062786 +25.8552530,eq=J2000&-c.rs=0.004 4.60 4.43 × 10−14 3.91 × 10−16 II/365/catwise -c=070.2062953 +25.8552378,eq=ICRS&-c.rs=0.004 4.60 4.46 × 10−14 8.47 × 10−16 II/368/sstsl2 -c=070.2062531 +25.8553357,eq=J2000&-c.rs=0.004 131 N. Varga, A. P. Joo, B. Koncz Acta Polytechnica λ νF(ν) Error Vizier table Vizier ID[µm] [Wm−2] [Wm−2] 4.60 4.54 × 10−14 8.47 × 10−16 I/353/gsc242 -c=070.20631586592 +25.85518403387,eq=ICRS&- c.rs=0.004 4.60 4.55 × 10−14 8.47 × 10−16 J/AJ/158/54/table1 recno=404 4.60 4.72 × 10−14 8.47 × 10−16 J/ApJ/784/126/table1 recno=338 4.60 4.74 × 10−14 9.12 × 10−16 II/311/wise WISE===J044049.50+255119.0&-c=070.206275 +25.855304,eq=J2000&-c. 5.73 2.90 × 10−14 1.73 × 10−15 II/332/c2d recno=5236589 5.73 2.92 × 10−14 0 × 10+0 II/368/sstsl2 -c=070.2062531 +25.8553357,eq=J2000&-c.rs=0.004 5.73 2.93 × 10−14 7.85 × 10−16 J/ApJ/784/126/table1 recno=338 5.73 3.04 × 10−14 1.41 × 10−15 J/ApJS/186/259/known recno=200 7.87 1.96 × 10−14 9.14 × 10−16 J/ApJS/186/259/known recno=200 7.87 1.97 × 10−14 0 × 10+0 II/368/sstsl2 -c=070.2062531 +25.8553357,eq=J2000&-c.rs=0.004 7.87 2.01 × 10−14 5.71 × 10−16 J/ApJ/784/126/table1 recno=338 7.87 2.07 × 10−14 1.07 × 10−15 II/332/c2d recno=5236589 11.56 1.09 × 10−14 1.82 × 10−16 I/353/gsc242 -c=070.20631586592 +25.85518403387,eq=ICRS&- c.rs=0.004 11.56 1.09 × 10−14 1.56 × 10−16 II/311/wise WISE===J044049.50+255119.0&-c=070.206275 +25.855304,eq=J2000&-c. 11.56 1.10 × 10−14 2.07 × 10−16 J/ApJ/784/126/table1 recno=338 11.56 1.16 × 10−14 1.82 × 10−16 II/368/sstsl2 -c=070.2062531 +25.8553357,eq=J2000&-c.rs=0.004 22.09 8.59 × 10−15 3.12 × 10−16 II/368/sstsl2 -c=070.2062531 +25.8553357,eq=J2000&-c.rs=0.004 22.09 8.70 × 10−15 3.26 × 10−16 J/AJ/158/54/table1 recno=404 22.09 8.73 × 10−15 3.26 × 10−16 II/328/allwise AllWISE===J044049.50+255119.0&-c=070.2062877 +25.8552863,eq=J200 22.09 8.74 × 10−15 3.26 × 10−16 I/353/gsc242 -c=070.20631586592 +25.85518403387,eq=ICRS&- c.rs=0.004 22.09 8.86 × 10−15 2.99 × 10−16 II/311/wise WISE===J044049.50+255119.0&-c=070.206275 +25.855304,eq=J2000&-c. 23.67 7.07 × 10−15 6.84 × 10−16 II/332/c2d recno=5236589 23.67 7.67 × 10−15 1.27 × 10−17 II/368/sstsl2 -c=070.2062531 +25.8553357,eq=J2000&-c.rs=0.004 23.67 7.74 × 10−15 2.79 × 10−16 J/ApJ/784/126/table1 recno=338 23.67 8.02 × 10−15 2.91 × 10−16 J/ApJS/186/259/known recno=200 23.67 3.06 × 10−13 1.14 × 10−14 J/ApJ/836/34/table2 recno=772 70.00 5.14 × 10−15 8.57 × 10−16 J/ApJ/849/63/ysos recno=119 71.42 4.28 × 10−15 8.81 × 10−16 J/ApJS/186/259/known recno=200 100.00 2.40 × 10−15 6.00 × 10−16 J/ApJ/849/63/ysos recno=119 155.90 1.30 × 10−15 J/ApJS/186/259/known recno=200 849.27 2.47 × 10−17 J/ApJ/773/168/table1 recno=109 880.01 2.38 × 10−17 J/ApJ/751/115/table6 recno=88 886.96 2.37 × 10−17 J/ApJ/771/129/table2 recno=165 1300.00 1.75 × 10−18 3.00 × 10−19 J/ApJ/872/158/table4 recno=171 1300.00 2.54 × 10−18 2.77 × 10−19 J/ApJ/872/158/table2 recno=45 1300.00 3.92 × 10−18 3.23 × 10−19 J/ApJ/872/158/table4 recno=170 1300.00 4.38 × 10−17 J/ApJ/773/168/table1 recno=109 1332.41 3.78 × 10−18 6.75 × 10−19 J/A+A/663/A98/tableg1 recno=26 1332.41 6.08 × 10−18 J/ApJ/771/129/table2 recno=165 Table 5. Data points on Figure 5 for XEST 07-024 from VizieR Photometry viewer. λ νF(ν) Error Vizier table Vizier ID[µm] [Wm−2] [Wm−2] 0.35 1.69 × 10−17 5.11 × 10−18 V/154/sdss16 -c=070.285107 +25.562459,eq=ICRS&-c.rs=0.004 0.35 1.70 × 10−17 5.20 × 10−18 IV/34/epic ID=247966607&-c=070.285121 +25.562456,eq=J2000&- c.rs=0.004 0.35 1.71 × 10−17 5.20 × 10−18 I/353/gsc242 -c=070.28496069846 +25.56243415687,eq=ICRS&- c.rs=0.004 0.35 2.26 × 10−17 5.37 × 10−18 V/154/sdss16 -c=070.285115 +25.562460,eq=ICRS&-c.rs=0.004 0.48 9.11 × 10−17 1.01 × 10−17 II/349/ps1 -c=070.284973280 +25.562431930,eq=J2000&-c.rs=0.004 0.48 4.63 × 10−17 2.18 × 10−18 V/154/sdss16 -c=070.285107 +25.562459,eq=ICRS&-c.rs=0.004 0.48 4.65 × 10−17 2.24 × 10−18 IV/34/epic ID=247966607&-c=070.285121 +25.562456,eq=J2000&- c.rs=0.004 0.48 4.76 × 10−17 2.24 × 10−18 V/154/sdss16 -c=070.285115 +25.562460,eq=ICRS&-c.rs=0.004 0.48 9.02 × 10−17 9.95 × 10−18 I/353/gsc242 -c=070.28496069846 +25.56243415687,eq=ICRS&- c.rs=0.004 0.50 1.97 × 10−16 1.01 × 10−17 I/350/gaiaedr3 -c=070.28495543413 +25.56243428514,eq=ICRS&- c.rs=0.004 0.50 1.97 × 10−16 1.01 × 10−17 I/355/gaiadr3 -c=070.28495543413 +25.56243428514,eq=ICRS&- c.rs=0.004 132 vol. 65 no. 1/2025 A study of X-ray point sources in Heiles Clouds 1 and 2 λ νF(ν) Error Vizier table Vizier ID[µm] [Wm−2] [Wm−2] 0.50 2.03 × 10−16 8.32 × 10−18 I/345/gaia2 -c=070.28496069846 +25.56243415687,eq=ICRS&- c.rs=0.004 0.58 1.19 × 10−15 5.15 × 10−18 I/350/gaiaedr3 -c=070.28495543413 +25.56243428514,eq=ICRS&- c.rs=0.004 0.58 1.23 × 10−15 5.15 × 10−18 I/355/gaiadr3 -c=070.28495543413 +25.56243428514,eq=ICRS&- c.rs=0.004 0.61 5.63 × 10−16 4.89 × 10−18 II/349/ps1 -c=070.284973280 +25.562431930,eq=J2000&-c.rs=0.004 0.62 1.13 × 10−15 0 × 10+0 I/345/gaia2 -c=070.28496069846 +25.56243415687,eq=ICRS&- c.rs=0.004 0.62 5.18 × 10−16 4.80 × 10−18 IV/34/epic ID=247966607&-c=070.285121 +25.562456,eq=J2000&- c.rs=0.004 0.62 5.18 × 10−16 4.80 × 10−18 V/154/sdss16 -c=070.285107 +25.562459,eq=ICRS&-c.rs=0.004 0.62 5.23 × 10−16 4.80 × 10−18 V/154/sdss16 -c=070.285115 +25.562460,eq=ICRS&-c.rs=0.004 0.62 5.52 × 10−16 4.80 × 10−18 I/353/gsc242 -c=070.28496069846 +25.56243415687,eq=ICRS&- c.rs=0.004 0.67 1.30 × 10−16 4.90 × 10−18 I/353/gsc242 -c=070.28496069846 +25.56243415687,eq=ICRS&- c.rs=0.004 0.67 1.30 × 10−16 4.90 × 10−18 J/ApJ/867/105/refcat2 -c=070.28496070 +25.56243416,eq=ICRS&-c.rs=0.004 0.67 9.31 × 10−16 J/ApJ/917/23/table1 recno=30496 0.67 9.58 × 10−16 0 × 10+0 I/353/gsc242 -c=070.28496069846 +25.56243415687,eq=ICRS&- c.rs=0.004 0.67 9.58 × 10−16 0 × 10+0 IV/38/tic -c=070.28512515484 +25.56243094699,eq=J2000&- c.rs=0.004 0.67 9.58 × 10−16 0 × 10+0 IV/39/tic82 -c=070.28512515484 +25.56243094699,eq=J2000&- c.rs=0.004 0.67 9.58 × 10−16 0 × 10+0 J/ApJ/867/105/refcat2 -c=070.28496070 +25.56243416,eq=ICRS&-c.rs=0.004 0.67 1.21 × 10−15 I/337/gaia -c=070.2849710755 +25.5624316983,eq=ICRS&-c.rs=0.004 0.67 1.21 × 10−15 8.91 × 10−18 I/339/hsoy -c=070.2849441512 +25.5624735697,eq=J2000&- c.rs=0.004 0.67 1.21 × 10−15 8.91 × 10−18 I/339/hsoy -c=070.2851234416 +25.5624466616,eq=J2000&- c.rs=0.004 0.67 3.55 × 10−15 1.78 × 10−17 J/ApJ/867/105/refcat2 -c=070.28496070 +25.56243416,eq=ICRS&-c.rs=0.004 0.67 3.56 × 10−15 1.78 × 10−17 I/353/gsc242 -c=070.28496069846 +25.56243415687,eq=ICRS&- c.rs=0.004 0.75 1.98 × 10−15 4.01 × 10−18 II/349/ps1 -c=070.284973280 +25.562431930,eq=J2000&-c.rs=0.004 0.76 2.64 × 10−15 1.57 × 10−17 I/350/gaiaedr3 -c=070.28495543413 +25.56243428514,eq=ICRS&- c.rs=0.004 0.76 2.64 × 10−15 1.57 × 10−17 I/355/gaiadr3 -c=070.28495543413 +25.56243428514,eq=ICRS&- c.rs=0.004 0.76 1.92 × 10−15 1.18 × 10−17 V/154/sdss16 -c=070.285107 +25.562459,eq=ICRS&-c.rs=0.004 0.76 1.93 × 10−15 1.18 × 10−17 V/154/sdss16 -c=070.285115 +25.562460,eq=ICRS&-c.rs=0.004 0.76 1.94 × 10−15 1.18 × 10−17 IV/34/epic ID=247966607&-c=070.285121 +25.562456,eq=J2000&- c.rs=0.004 0.76 1.95 × 10−15 3.93 × 10−18 I/353/gsc242 -c=070.28496069846 +25.56243415687,eq=ICRS&- c.rs=0.004 0.77 2.69 × 10−15 1.55 × 10−17 I/345/gaia2 -c=070.28496069846 +25.56243415687,eq=ICRS&- c.rs=0.004 0.87 4.12 × 10−15 0 × 10+0 II/349/ps1 -c=070.284973280 +25.562431930,eq=J2000&-c.rs=0.004 0.88 4.45 × 10−15 0 × 10+0 II/319/gcs9 -c=070.285011 +25.562462,eq=J2000&-c.rs=0.004 0.90 3.96 × 10−15 0 × 10+0 I/353/gsc242 -c=070.28496069846 +25.56243415687,eq=ICRS&- c.rs=0.004 0.90 4.92 × 10−15 3.32 × 10−17 V/154/sdss16 -c=070.285115 +25.562460,eq=ICRS&-c.rs=0.004 0.90 4.92 × 10−15 3.32 × 10−17 V/154/sdss16 -c=070.285107 +25.562459,eq=ICRS&-c.rs=0.004 0.90 4.95 × 10−15 3.32 × 10−17 IV/34/epic ID=247966607&-c=070.285121 +25.562456,eq=J2000&- c.rs=0.004 0.96 6.59 × 10−15 3.12 × 10−17 II/349/ps1 -c=070.284973280 +25.562431930,eq=J2000&-c.rs=0.004 1.03 7.74 × 10−15 2.91 × 10−17 II/319/gcs9 -c=070.285011 +25.562462,eq=J2000&-c.rs=0.004 1.24 1.27 × 10−14 2.90 × 10−16 II/368/sstsl2 -c=070.2850393 +25.5624436,eq=J2000&-c.rs=0.004 1.24 1.28 × 10−14 I/297/out NOMAD1===1155-0059400&-c=070.2847000 +25.5625917,eq=J2000&-c.rs= 1.24 1.28 × 10−14 2.90 × 10−16 I/317/sample PPMXL=3103086006484443817&-c=070.285025 +25.562486,eq=J2000&-c.r 1.24 1.28 × 10−14 2.90 × 10−16 I/317/sample PPMXL=3103086006526005598&-c=070.285109 +25.562451,eq=J2000&-c.r 1.24 1.28 × 10−14 2.90 × 10−16 I/339/hsoy -c=070.2849441512 +25.5624735697,eq=J2000&- c.rs=0.004 1.24 1.28 × 10−14 2.90 × 10−16 I/339/hsoy -c=070.2851234416 +25.5624466616,eq=J2000&- c.rs=0.004 1.24 1.28 × 10−14 2.90 × 10−16 II/311/wise WISE===J044108.40+253344.8&-c=070.285030 +25.562467,eq=J2000&-c. 1.24 1.28 × 10−14 2.90 × 10−16 II/328/allwise AllWISE===J044108.40+253344.8&-c=070.2850171 +25.5624449,eq=J200 133 N. Varga, A. P. Joo, B. Koncz Acta Polytechnica λ νF(ν) Error Vizier table Vizier ID[µm] [Wm−2] [Wm−2] 1.24 1.28 × 10−14 2.90 × 10−16 II/360/catalog -c=070.284961 +25.562434,eq=ICRS&-c.rs=0.004 1.24 1.28 × 10−14 2.66 × 10−16 J/ApJ/867/105/refcat2 -c=070.28496070 +25.56243416,eq=ICRS&-c.rs=0.004 1.24 1.28 × 10−14 2.90 × 10−16 I/353/gsc242 -c=070.28496069846 +25.56243415687,eq=ICRS&- c.rs=0.004 1.24 1.28 × 10−14 2.90 × 10−16 IV/34/epic ID=247966607&-c=070.285121 +25.562456,eq=J2000&- c.rs=0.004 1.25 1.32 × 10−14 2.40 × 10−17 II/319/gcs9 -c=070.285011 +25.562462,eq=J2000&-c.rs=0.004 1.25 1.28 × 10−14 3.12 × 10−16 II/246/out 2MASS===04410842+2533448 &-c=070.285121 +25.562456,eq=J2000&-c.r 1.25 1.29 × 10−14 2.88 × 10−16 II/246/out 2MASS===04410842+2533448 &-c=070.285121 +25.562456,eq=J2000&-c.r 1.25 1.29 × 10−14 2.88 × 10−16 IV/38/tic -c=070.28512515484 +25.56243094699,eq=J2000&- c.rs=0.004 1.25 1.29 × 10−14 2.88 × 10−16 IV/39/tic82 -c=070.28512515484 +25.56243094699,eq=J2000&- c.rs=0.004 1.63 1.97 × 10−14 5.52 × 10−16 II/246/out 2MASS===04410842+2533448 &-c=070.285121 +25.562456,eq=J2000&-c.r 1.63 1.99 × 10−14 3.68 × 10−16 II/246/out 2MASS===04410842+2533448 &-c=070.285121 +25.562456,eq=J2000&-c.r 1.63 1.99 × 10−14 3.68 × 10−16 IV/38/tic -c=070.28512515484 +25.56243094699,eq=J2000&- c.rs=0.004 1.63 1.99 × 10−14 3.68 × 10−16 IV/39/tic82 -c=070.28512515484 +25.56243094699,eq=J2000&- c.rs=0.004 1.65 1.89 × 10−14 3.64 × 10−16 II/368/sstsl2 -c=070.2850393 +25.5624436,eq=J2000&-c.rs=0.004 1.65 1.98 × 10−14 I/297/out NOMAD1===1155-0059400&-c=070.2847000 +25.5625917,eq=J2000&-c.rs= 1.65 1.98 × 10−14 5.45 × 10−16 I/317/sample PPMXL=3103086006484443817&-c=070.285025 +25.562486,eq=J2000&-c.r 1.65 1.98 × 10−14 5.45 × 10−16 I/317/sample PPMXL=3103086006526005598&-c=070.285109 +25.562451,eq=J2000&-c.r 1.65 1.98 × 10−14 5.45 × 10−16 I/339/hsoy -c=070.2849441512 +25.5624735697,eq=J2000&- c.rs=0.004 1.65 1.98 × 10−14 5.45 × 10−16 I/339/hsoy -c=070.2851234416 +25.5624466616,eq=J2000&- c.rs=0.004 1.65 1.98 × 10−14 5.45 × 10−16 I/353/gsc242 -c=070.28496069846 +25.56243415687,eq=ICRS&- c.rs=0.004 1.65 1.98 × 10−14 5.45 × 10−16 II/311/wise WISE===J044108.40+253344.8&-c=070.285030 +25.562467,eq=J2000&-c. 1.65 1.98 × 10−14 5.45 × 10−16 II/328/allwise AllWISE===J044108.40+253344.8&-c=070.2850171 +25.5624449,eq=J200 1.65 1.98 × 10−14 5.45 × 10−16 II/360/catalog -c=070.284961 +25.562434,eq=ICRS&-c.rs=0.004 1.65 1.98 × 10−14 5.45 × 10−16 IV/34/epic ID=247966607&-c=070.285121 +25.562456,eq=J2000&- c.rs=0.004 1.65 1.98 × 10−14 3.64 × 10−16 J/ApJ/867/105/refcat2 -c=070.28496070 +25.56243416,eq=ICRS&-c.rs=0.004 2.16 1.44 × 10−14 2.77 × 10−16 II/368/sstsl2 -c=070.2850393 +25.5624436,eq=J2000&-c.rs=0.004 2.16 1.48 × 10−14 2.77 × 10−16 I/317/sample PPMXL=3103086006484443817&-c=070.285025 +25.562486,eq=J2000&-c.r 2.16 1.48 × 10−14 2.77 × 10−16 I/317/sample PPMXL=3103086006526005598&-c=070.285109 +25.562451,eq=J2000&-c.r 2.16 1.48 × 10−14 2.77 × 10−16 I/353/gsc242 -c=070.28496069846 +25.56243415687,eq=ICRS&- c.rs=0.004 2.16 1.48 × 10−14 2.77 × 10−16 II/311/wise WISE===J044108.40+253344.8&-c=070.285030 +25.562467,eq=J2000&-c. 2.16 1.48 × 10−14 2.77 × 10−16 II/328/allwise AllWISE===J044108.40+253344.8&-c=070.2850171 +25.5624449,eq=J200 2.16 1.48 × 10−14 2.77 × 10−16 IV/34/epic ID=247966607&-c=070.285121 +25.562456,eq=J2000&- c.rs=0.004 2.16 1.48 × 10−14 2.77 × 10−16 IV/38/tic -c=070.28512515484 +25.56243094699,eq=J2000&- c.rs=0.004 2.16 1.48 × 10−14 2.77 × 10−16 IV/39/tic82 -c=070.28512515484 +25.56243094699,eq=J2000&- c.rs=0.004 2.19 1.41 × 10−14 2.74 × 10−16 II/246/out 2MASS===04410842+2533448 &-c=070.285121 +25.562456,eq=J2000&-c.r 2.19 1.41 × 10−14 2.74 × 10−16 II/246/out 2MASS===04410842+2533448 &-c=070.285121 +25.562456,eq=J2000&-c.r 2.20 1.27 × 10−14 1.36 × 10−17 II/319/gcs9 -c=070.285011 +25.562462,eq=J2000&-c.rs=0.004 2.20 1.30 × 10−14 1.36 × 10−17 II/316/gps6 -c=070.285001 +25.562460,eq=ICRS&-c.rs=0.004 2.20 1.30 × 10−14 1.36 × 10−17 II/316/gps6 -c=070.285001 +25.562460,eq=ICRS&-c.rs=0.004 2.20 1.31 × 10−14 1.36 × 10−17 II/316/gps6 -c=070.285001 +25.562460,eq=ICRS&-c.rs=0.004 3.35 5.42 × 10−15 1.16 × 10−16 II/368/sstsl2 -c=070.2850393 +25.5624436,eq=J2000&-c.rs=0.004 3.35 5.45 × 10−15 6.26 × 10−17 II/365/catwise -c=070.2849803 +25.5624328,eq=ICRS&-c.rs=0.004 134 vol. 65 no. 1/2025 A study of X-ray point sources in Heiles Clouds 1 and 2 λ νF(ν) Error Vizier table Vizier ID[µm] [Wm−2] [Wm−2] 3.35 5.47 × 10−15 1.16 × 10−16 II/311/wise WISE===J044108.40+253344.8&-c=070.285030 +25.562467,eq=J2000&-c. 3.35 5.49 × 10−15 8.95 × 10−18 II/363/unwise -c=070.2849805 +25.5624425,eq=J2000&-c.rs=0.004 3.35 5.50 × 10−15 1.16 × 10−16 I/353/gsc242 -c=070.28496069846 +25.56243415687,eq=ICRS&- c.rs=0.004 3.35 5.50 × 10−15 1.16 × 10−16 II/328/allwise AllWISE===J044108.40+253344.8&-c=070.2850171 +25.5624449,eq=J200 3.35 5.50 × 10−15 1.16 × 10−16 IV/38/tic -c=070.28512515484 +25.56243094699,eq=J2000&- c.rs=0.004 3.35 5.50 × 10−15 1.16 × 10−16 IV/39/tic82 -c=070.28512515484 +25.56243094699,eq=J2000&- c.rs=0.004 3.55 4.71 × 10−15 8.44 × 10−18 II/368/sstsl2 -c=070.2850393 +25.5624436,eq=J2000&-c.rs=0.004 4.49 2.53 × 10−15 6.67 × 10−18 II/368/sstsl2 -c=070.2850393 +25.5624436,eq=J2000&-c.rs=0.004 4.60 2.28 × 10−15 6.52 × 10−18 II/363/unwise -c=070.2849805 +25.5624425,eq=J2000&-c.rs=0.004 4.60 2.35 × 10−15 5.21 × 10−17 II/368/sstsl2 -c=070.2850393 +25.5624436,eq=J2000&-c.rs=0.004 4.60 2.36 × 10−15 1.96 × 10−17 II/365/catwise -c=070.2849803 +25.5624328,eq=ICRS&-c.rs=0.004 4.60 2.38 × 10−15 5.21 × 10−17 II/311/wise WISE===J044108.40+253344.8&-c=070.285030 +25.562467,eq=J2000&-c. 4.60 2.39 × 10−15 5.21 × 10−17 I/353/gsc242 -c=070.28496069846 +25.56243415687,eq=ICRS&- c.rs=0.004 4.60 2.39 × 10−15 5.21 × 10−17 II/328/allwise AllWISE===J044108.40+253344.8&-c=070.2850171 +25.5624449,eq=J200 4.60 2.39 × 10−15 5.21 × 10−17 IV/38/tic -c=070.28512515484 +25.56243094699,eq=J2000&- c.rs=0.004 4.60 2.39 × 10−15 5.21 × 10−17 IV/39/tic82 -c=070.28512515484 +25.56243094699,eq=J2000&- c.rs=0.004 5.73 1.39 × 10−15 1.05 × 10−17 II/368/sstsl2 -c=070.2850393 +25.5624436,eq=J2000&-c.rs=0.004 7.87 5.71 × 10−16 7.62 × 10−18 II/368/sstsl2 -c=070.2850393 +25.5624436,eq=J2000&-c.rs=0.004 11.56 1.10 × 10−16 3.94 × 10−17 I/353/gsc242 -c=070.28496069846 +25.56243415687,eq=ICRS&- c.rs=0.004 11.56 1.10 × 10−16 3.94 × 10−17 II/328/allwise AllWISE===J044108.40+253344.8&-c=070.2850171 +25.5624449,eq=J200 11.56 1.10 × 10−16 3.94 × 10−17 IV/38/tic -c=070.28512515484 +25.56243094699,eq=J2000&- c.rs=0.004 11.56 1.10 × 10−16 3.94 × 10−17 IV/39/tic82 -c=070.28512515484 +25.56243094699,eq=J2000&- c.rs=0.004 11.56 1.17 × 10−16 4.12 × 10−17 II/368/sstsl2 -c=070.2850393 +25.5624436,eq=J2000&-c.rs=0.004 11.56 3.53 × 10−16 3.63 × 10−17 II/311/wise WISE===J044108.40+253344.8&-c=070.285030 +25.562467,eq=J2000&-c. 22.09 3.22 × 10−16 1.57 × 10−16 II/311/wise WISE===J044108.40+253344.8&-c=070.285030 +25.562467,eq=J2000&-c. 22.09 4.61 × 10−16 II/368/sstsl2 -c=070.2850393 +25.5624436,eq=J2000&-c.rs=0.004 22.09 4.68 × 10−16 I/353/gsc242 -c=070.28496069846 +25.56243415687,eq=ICRS&- c.rs=0.004 22.09 4.68 × 10−16 II/328/allwise AllWISE===J044108.40+253344.8&-c=070.2850171 +25.5624449,eq=J200 22.09 4.68 × 10−16 IV/38/tic -c=070.28512515484 +25.56243094699,eq=J2000&- c.rs=0.004 22.09 4.68 × 10−16 IV/39/tic82 -c=070.28512515484 +25.56243094699,eq=J2000&- c.rs=0.004 135 Acta Polytechnica 65(1):119–135, 2025 1 Introduction 2 Data and methods 2.1 Heiles Cloud 2 2.2 Taurus Molecular Cloud 1 (TMC1) 2.3 Matching sources in HCL 2 2.4 Heiles Cloud 1 2.5 Hardness ratio 3 Results 3.1 Polarisation 3.2 Comparison Acknowledgements References A