A study of X-ray point sources in Heiles Clouds 1 and 2

Authors

  • Nóra Varga Eötvös Loránd University, Department of Astronomy, Pázmány Péter sétány 1/A, 1117 Budapest, Hungary
  • András Péter Joó Eötvös Loránd University, Department of Astronomy, Pázmány Péter sétány 1/A, 1117 Budapest, Hungary
  • Bendegúz Koncz Eötvös Loránd University, Department of Astronomy, Pázmány Péter sétány 1/A, 1117 Budapest, Hungary; Doctoral School of Physics at University of Debrecen, Bem tér 18/B, 4026 Debrecen, Hungary

DOI:

https://doi.org/10.14311/AP.2025.65.0119

Keywords:

ISM, YSO, polarisation, magnetic field

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.

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References

R. C. Kennicutt, N. J. Evans. Star formation in the Milky Way and nearby galaxies. Annual Review of Astronomy & Astrophysics 50:531–608, 2012. https://doi.org/10.1146/annurev-astro-081811-125610

A. Bacmann, P. Andre, J.-L. Puget, et al. An ISOCAM absorption survey of the structure of pre-stellar cloud cores. Astronomy & Astrophysics 361:555–580, 2000. https://doi.org/10.48550/arXiv.astro-ph/0006385

A. M. Stutz, J. H. Bieging, G. H. Rieke, et al. Spitzer observations of a 24 μm shadow: Bok globule CB 190. The Astrophysical Journal 665(1):466, 2007. https://doi.org/10.1086/519488

P. André, A. Men’shchikov, S. Bontemps, et al. From filamentary clouds to prestellar cores to the stellar IMF: Initial highlights from the Herschel Gould belt survey. Astronomy & Astrophysics 518:L102, 2010. https://doi.org/10.1051/0004-6361/201014666

T. Preibisch, E. D. Feigelson. The evolution of X-ray emission in young stars. The Astrophysical Journal Supplement Series 160(2):390, 2005. https://doi.org/10.1086/432094

E. D. Feigelson, L. K. Townsley, P. S. Broos, et al. Overview of the Massive Young Star-forming Complex study in Infrared and X-Ray (MYStIX) project. The Astrophysical Journal Supplement Series 209(2):26, 2013. https://doi.org/10.1088/0067-0049/209/2/26

L. K. Townsley, P. S. Broos, G. P. Garmire, et al. The massive star-forming regions omnibus X-ray catalog. The Astrophysical Journal Supplement Series 213(1):1, 2014. https://doi.org/10.1088/0067-0049/213/1/1

C. E. Heiles. Normal OH emission and interstellar dust clouds. The Astrophysical Journal 151:919, 1968. https://doi.org/10.1086/149493

B. T. Lynds. Catalogue of dark nebulae. The Astrophysical Journal Supplement Series 7:1, 1962. https://doi.org/10.1086/190072

Z. T. Kiss, L. V. Tóth, O. Krause, et al. Star formation in the Cepheus Flare region: Implications from morphology and infrared properties of optically selected clouds. Astronomy & Astrophysics 453(3):923–936, 2006. https://doi.org/10.1051/0004-6361:20053235

M. Szilágyi, M. Kun, P. Ábrahám. The Gaia view of the Cepheus Flare. Monthly Notices of the Royal Astronomical Society 505(4):5164–5182, 2021. https://doi.org/10.1093/mnras/stab1496

L. V. Toth, C. M. Walmsley. Star formation in L 1251. II. “The next generation” – NH3 cores. Astronomy & Astrophysics 311:981–988, 1996.

L. Pasztor, L. V. Toth, L. G. Balazs. Searching for embedded clusters in the Cepheus-Cassiopeiaregion. Astronomy & Astrophysics 268:108–115, 1993.

M. Kun, T. Prusti. Star formation in L 1251: Distance and members. Astronomy & Astrophysics 272:235–242, 1993.

V. L. Toth, C. M. Walmsley. Water masers in L1251. Information Bulletin on Variable Stars 4107:1, 1994.

L. V. Toth, M. Kun. New water maser in L1251. Information Bulletin on Variable Stars 4492:1, 1997.

L. V. Tóth, A. Horváth, L. K. Haikala. Low velocity shock-cloud encounters II. Observations and interpretation. Astrophysics and Space Science 233(1):175–179, 1995. https://doi.org/10.1007/BF00627347

E. Sharma, G. Maheswar, S. Dib. Cloud motion and magnetic fields: Four clouds in the Cepheus Flare region. Astronomy & Astrophysics 658:A55, 2022. [Erratum: Astronomy & Astrophysics 659:C2, 2022]. https://doi.org/10.1051/0004-6361/202140495

L. G. Balázs, P. Ábrahám, M. Kun, et al. Star count analysis of the interstellar matter in the region of L1251. Astronomy & Astrophysics 425(1):133–141, 2004. https://doi.org/10.1051/0004-6361:20047059

C. Zucker, J. S. Speagle, E. F. Schlafly, et al. A compendium of distances to molecular clouds in the Star formation handbook. Astronomy & Astrophysics 633:A51, 2020. https://doi.org/10.1051/0004-6361/201936145

M. Zhang. Distances to nearby molecular clouds traced by young stars. The Astrophysical Journal Supplement Series 265(2):59, 2023. https://doi.org/10.3847/1538-4365/acc1e8

L. V. Tóth, M. Haas, D. Lemke, et al. Very cold cores in the Taurus molecular ring as seen by ISO. Astronomy & Astrophysics 420(2):533–546, 2004. https://doi.org/10.1051/0004-6361:20035611

D. Apai, L. V. Tóth, T. Henning, et al. HST/NICMOS observations of a proto-brown dwarf candidate. Astronomy & Astrophysics 433(2):L33–L36, 2005. https://doi.org/10.1051/0004-6361:200500098

Ł. Tychoniec, M. L. van Gelder, E. F. van Dishoeck, et al. JWST Observations of Young protoStars (JOYS). Linked accretion and ejection in a class I protobinary system. Astronomy & Astrophysics 687:A36, 2024. https://doi.org/10.1051/0004-6361/202348889

L. V. Tóth, O. Fehér, M. Juvela, et al. HCL1 and HCL2 – low mass star formation in violent and quiet environments. Proceedings of the International Astronomical Union 14(S345):333–334, 2018. https://doi.org/10.1017/S1743921319001741

M. J. Page, C. Brindle, A. Talavera, et al. The XMM-Newton serendipitous ultraviolet source survey catalogue. Monthly Notices of the Royal Astronomical Society 426(2):903–926, 2012. https://doi.org/10.1111/j.1365-2966.2012.21706.x

M. Güdel, K. R. Briggs, K. Arzner, et al. The XMMNewton extended survey of the Taurus molecular cloud (XEST). Astronomy & Astrophysics 468(2):353–377, 2007. https://doi.org/10.1051/0004-6361:20065724

C. J. Lada. Star formation: From OB associations to protostars. In M. Peimbert, J. Jugaku (eds.), Star Forming Regions, vol. 115, p. 1. 1987.

N. A. Webb, M. Coriat, I. Traulsen, et al. The XMM-Newton serendipitous survey. IX. The fourth XMM-Newton serendipitous source catalogue. Astronomy & Astrophysics 641:A136, 2020. https://doi.org/10.1051/0004-6361/201937353

E. W. Flesch. The millions of optical-radio/X-ray associations (MORX) catalogue, v2. The Open Journal of Astrophysics 7, 2024. https://doi.org/10.21105/astro.2308.01507

D. Stern, R. J. Assef, D. J. Benford, et al. Mid-infrared selection of active galactic nuclei with the wide-field infrared survey explorer. I. Characterizing WISE-selected active galactic nuclei in COSMOS. The Astrophysical Journal 753(1):30, 2012. https://doi.org/10.1088/0004-637X/753/1/30

V. S. Pérez-Díaz, J. R. Martínez-Galarza, A. Caicedo, R. D’Abrusco. Unsupervised machine learning for the classification of astrophysical X-ray sources. Monthly Notices of the Royal Astronomical Society 528(3):4852–4871, 2024. https://doi.org/10.1093/mnras/stae260

M. Guedel, K. R. Briggs, K. Arzner, et al. VizieR online data catalog: XMM-Newton extended survey of Taurus: J/A+A/468/353, 2007. https://doi.org/10.26093/cds/vizier.34680353

L. Davis, Jr., J. L. Greenstein. The polarization of starlight by aligned dust grains. The Astrophysical Journal 114:206, 1951. https://doi.org/10.1086/145464

H. Hildebrand, J. A. Davidson, J. L. Dotson, et al. Erratum: A primer on far-infrared polarimetry. Publications of the Astronomical Society of the Pacific 112(778):1621, 2000. https://doi.org/10.1086/317728

M. Wenger, F. Ochsenbein, D. Egret, et al. The SIMBAD astronomical database. The CDS reference database for astronomical objects. Astronomy and Astrophysics Supplement Series 143:9–22, 2000. https://doi.org/10.1051/aas:2000332

Bonnarel, F., Fernique, P., Bienaymé, O., et al. The ALADIN interactive sky atlas – A reference tool for identification of astronomical sources. Astronomy and Astrophysics Supplement Series 143(1):33–40, 2000. https://doi.org/10.1051/aas:2000331

Ochsenbein, F., Bauer, P., Marcout, J. The VizieR database of astronomical catalogues. Astronomy and Astrophysics Supplement Series 143(1):23–32, 2000. https://doi.org/10.1051/aas:2000169

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Published

2025-03-06

How to Cite

Varga, N., Joó, A. P., & Koncz, B. (2025). A study of X-ray point sources in Heiles Clouds 1 and 2. Acta Polytechnica, 65(1), 119-135. https://doi.org/10.14311/AP.2025.65.0119