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Spectroscopic and Photometric Study of the S-type Mira V667 Cassiopeiae and the Carbon Star OR Cephei
DOI: 10.48550/arXiv.2407.01719 Bibcode: 2024JAVSO..52...96B

Boyd, D.

We report on spectroscopic and photometric observations of the S-type Mira V667 Cas and the carbon star Mira OR Cep recorded during one pulsation cycle of each star in 2022. Spectra are calibrated in absolute flux using concurrent photometry. We present measurements of V and Ic magnitudes and V-Ic color index, classify spectra in the revised MK sy…

2024 Journal of the American Association of Variable Star Observers (JAAVSO)
Gaia 0
Precise measurement of pion-bump structure using future MeV gamma-ray detectors
DOI: 10.1103/PhysRevD.110.063026 Bibcode: 2024PhRvD.110f3026L

Liu, Jiahao; Liu, Bing; Yang, Ruizhi

The pion-bump structure in the γ-ray spectrum is a direct proof for the hadronic origin of the γ rays, and thus the decisive evidence for the acceleration of hadronic cosmic…

2024 Physical Review D
INTEGRAL 0
The Goldstone Apple Valley Radio Telescope (GAVRT) Search for Extra Terrestrial Intelligence (SETI)
DOI: 10.1088/1538-3873/ad2f4f Bibcode: 2024PASP..136d4502G

Gorjian, Varoujan; Lazio, Joseph; Levin, Steven +6 more

This paper reports the results from a student-led Search for Extraterrestrial Intelligence (SETI), also known as technosignatures, targeting the plane of the Milky Way as a part of the Goldstone Apple Valley Radio Telescope (GAVRT) collaboration between the Lewis Center for Educational Research (LCER) and the Jet Propulsion Laboratory. Students as…

2024 Publications of the Astronomical Society of the Pacific
Gaia 0
Multiwavelength identification of millisecond pulsar candidates in the Galactic bulge
DOI: 10.1051/0004-6361/202449473 Bibcode: 2024A&A...690A.330B

Kerr, M.; Calore, F.; Schinzel, F. K. +4 more

Context. The existence of a population of millisecond pulsars in the Galactic bulge is supported, along with other evidence, by the Fermi GeV excess, an anomalous γ-ray emission detected almost 15 years ago in the direction of the Galactic center. However, radio surveys searching for pulsations have not yet revealed bulge millisecond pulsars. Aims…

2024 Astronomy and Astrophysics
XMM-Newton 0
Unveiling the short and faint X-ray transient nature of IGR J17419–2802
DOI: 10.1051/0004-6361/202450791 Bibcode: 2024A&A...690A.260S

Sidoli, L.; Sguera, V.

We report new X-ray results from the INTErnational Gamma-Ray Astrophysics Laboratory (INTEGRAL), Swift, Chandra, and XMM–Newton observations of the hitherto poorly studied unidentified X-ray transient IGR J17419‑2802. We studied in detail the temporal, spectral, and energetic properties of three hard X-ray outbursts detected above 20 keV by INTEGR…

2024 Astronomy and Astrophysics
Gaia INTEGRAL XMM-Newton 0
Old massive clusters (and a nuclear star cluster?) in the tidal tails of NGC 5238
DOI: 10.1051/0004-6361/202451810 Bibcode: 2024A&A...690L..12B

Cignoni, M.; Tosi, M.; Bellazzini, M. +12 more

New, deep HST photometry allowed us to identify and study eight compact and bright (MV ≤ ‑5.8) star clusters in the outskirts of the star-forming isolated dwarf galaxy NGC 5238 (M* ≃ 108 M). Five of these clusters are new discoveries, and six appear projected onto and/or aligned with the tidal tails rec…

2024 Astronomy and Astrophysics
eHST 0
NGC 1856: Using Machine Learning Techniques to Uncover Detailed Stellar Abundances from MUSE Data
DOI: 10.3847/1538-3881/ad3f1b Bibcode: 2024AJ....167..265A

Hernandez, S.; Wang, Z.; Matteucci, F. +5 more

We present the first application of the novel approach based on data-driven machine learning methods applied to Multi-Unit Spectroscopic Explorer (MUSE) field data to derive stellar abundances of star clusters. MUSE has been used to target more than 10,000 fields, and it is unique in its ability to study dense stellar fields such as stellar cluste…

2024 The Astronomical Journal
eHST 0
Fractal Effects of the Stellar Medium in the Vicinity of the Sun According to Gaia DR2 Data
DOI: 10.1134/S1990341324600601 Bibcode: 2024AstBu..79..504O

Rastorguev, A. S.; Ostashova, M. L.

In this paper, we study the fractal properties of the stellar medium in the solar vicinity based on the Gaia DR2 data for 200 000 stars of all spectral types at distances from 1 to 100 pc from the Sun. We consider the main stages of the development of ideas about the fractal structure in the stellar medium of galaxies. Analysis of the spatial dist…

2024 Astrophysical Bulletin
Gaia 0
BST1047+1156: A (Failing) Ultradiffuse Tidal Dwarf in the Leo I Group
DOI: 10.3847/1538-4357/ad1cef Bibcode: 2024ApJ...964...67M

Mihos, J. Christopher; Durrell, Patrick R.; McGaugh, Stacy S. +2 more

We use deep Hubble Space Telescope imaging to study the resolved stellar populations in BST1047+1156, a gas-rich, ultradiffuse dwarf galaxy found in the intragroup environment of the Leo I galaxy group. While our imaging reaches approximately two magnitudes below the tip of the red giant branch at the Leo I distance of 11 Mpc, we find no evidence …

2024 The Astrophysical Journal
eHST 0
Long-Term Variation of the Galactic Cosmic Ray Radiation Dose Rates
DOI: 10.1029/2023SW003804 Bibcode: 2024SpWea..2203804L

Qin, G.; Shen, Z. -N.; Lyu, D.

In this work, a model for calculating the galactic cosmic rays (GCRs) radiation dose rate is developed. The model is based on a GCR modulation model, which is established by Shen and Qin, and the fluence-dose conversion coefficients (FDCCs) published by the International Commission on Radiological Protection (ICRP). With the model, the radiation a…

2024 Space Weather
Ulysses 0