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Related papers: Long-term Stellar Variability in the Galactic Cent…

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We report here CCD $I$-band time-series photometry of a young (2$-$5 Myr) cluster NGC 2282 to identify and understand the variability of pre-main-sequence (PMS) stars. The $I$-band photometry, down to $\sim$ 20.5 mag, enables us to probe…

Astrophysics of Galaxies · Physics 2018-04-04 Somnath Dutta , Soumen Mondal , Santosh Joshi , Jessy Jose , Ramkrishna Das , Supriyo Ghosh

We report the discovery of a previously unknown massive Galactic star cluster at l=29.22, b=-0.20. Identified visually in mid-IR images from the Spitzer GLIMPSE survey, the cluster contains at least 8 late-type supergiants, based on…

Astrophysics of Galaxies · Physics 2009-11-13 Michael J. Alexander , Henry A. Kobulnicky , Dan P. Clemens , Katherine Jameson , April Pinnick , Michael Pavel

A photometric study of variable stars in the field of old open cluster NGC 188 is discussed. Observations were carried out in two bands R and I for 5513 stars up to R = 17 mag in the field of 1.5 x 1.5 grad. around the cluster. The…

Solar and Stellar Astrophysics · Physics 2013-04-19 A. A. Popov , V. V. Krushinsky , E. A. Avvakumova , A. Y. Burdanov , A. F. Punanova , I. S. Zalozhnih

We have conducted a large-scale survey of the northern plane using Kiso Wide Field Camera attached to Schmidt telescope at Kiso observatory. The KISOGP (KWFC Intensive Survey of the Galactic Plane) project have made 40-70 epoch observations…

Solar and Stellar Astrophysics · Physics 2017-09-13 Noriyuki Matsunaga

Utilizing a decade-long unTimely dataset, supplemented by multi-band data from archives, we search for young stellar objects (YSOs) with variations larger than one magnitude in W1 band within a region of 110 square degrees in the Galactic…

Solar and Stellar Astrophysics · Physics 2024-06-27 Jiaxun Li , Tinggui Wang

The VVV survey has allowed for an unprecedented number of multi-epoch observations of the southern Galactic plane. In a recent paper,13 massive young stellar objects(MYSOs) have already been identified within the highly variable(\Delta Ks >…

Because of strong and spatially highly variable interstellar extinction and extreme source crowding, the faint (K>15) stellar population in the Milky Way's nuclear cluster is still poorly studied. RR Lyrae stars provide us with a tool to…

Long-period variables (LPVs) are evolved red giant and supergiant stars whose pulsations provide unique insights into late stages of stellar evolution and serve as essential tools in modern astrophysics. Their period-luminosity and…

Solar and Stellar Astrophysics · Physics 2026-01-29 Dorota M. Skowron , Igor Soszyński

We present results of variability search in the field of the young open cluster NGC 1502. Eight variable stars were discovered. Of six other stars in the observed field that were suspected for variability, we confirm variability of two,…

Solar and Stellar Astrophysics · Physics 2009-12-04 G. Michalska , A. Pigulski , M. Stęślicki , A. Narwid

Based on multicolor photometry from the 2MASS and Tycho-2 catalogues, we have produced a sample of 38 368 branch red giants that has less than 1\% of admixtures and is complete within 500 pc of the Sun. The sample includes 30 671 K giants,…

Solar and Stellar Astrophysics · Physics 2016-07-06 George Gontcharov

This paper is the second in a series describing the southern Galactic Disk Survey (GDS) performed at the Universit\"atssternwarte Bochum near Cerro Armazones in Chile. Haas et al. (2012, Paper I) presented the survey design and a the…

Solar and Stellar Astrophysics · Physics 2015-08-10 M. Hackstein , Ch. Fein , M. Haas , M. Ramolla , F. Pozo Nunez , A. Barr Dominguez , L. Kaderhandt , K. Thomsch , N. Niedworok , Ch. Westhues , R. Chini

We present a new analysis of the long-period variables in the Large Magellanic Cloud (LMC) from the MACHO Variable Star Catalog. Three-quarters of our sample of evolved, variable stars have periodic light curves. We characterize the stars…

Astrophysics · Physics 2010-03-01 Oliver J. Fraser , Suzanne L. Hawley , Kem H. Cook

The first variable star catalogue in a giant elliptical galaxy NGC 5128 (Centaurus A) is presented. Using multi-epoch observations with ISAAC at the VLT we have detected 1504 red variables in two halo fields covering 10.46 arcmin square.…

Astrophysics · Physics 2009-11-07 M. Rejkuba , D. Minniti , D. R. Silva

We study the evolution and observability of young compact star clusters within about 200pc of the Galactic center. Calculations are performed using direct N-body integration on the GRAPE-4, including the effects of both stellar and binary…

Astrophysics · Physics 2009-10-31 Simon Portegies Zwart , Junichiro Makino , Stephen McMillan , Piet Hut

Since 1999, a radial velocity survey of 179 red giant stars is ongoing at Lick Observatory with a one month cadence. At present ~20-100 measurements have been collected per star with an accuracy of 5 to 8 m/s. Of the stars monitored, 145…

Astrophysics · Physics 2008-11-26 S. Hekker , I. A. G. Snellen , C. Aerts , A. Quirrenbach , S. Reffert , D. S. Mitchell

We present a new sample of 525 Mira variables in the direction of the Galactic Bulge, expanding on previous samples of 69 and 500 objects, respectively, and thereby concluding our search for new Mira variables in the MACHO Galactic Bulge…

Solar and Stellar Astrophysics · Physics 2013-07-30 Klaus Bernhard , Stefan Huemmerich

New candidate variable stars have been identified in the Small Magellanic Cloud cluster NGC121, by applying both the image subtraction technique (ISIS, Alard 2000) and the Welch & Stetson (1993) detection method to HST WFPC2 archive and ACS…

Astrophysics · Physics 2009-06-23 G. Fiorentino , R. Contreras , G. Clementini , K. Glatt , E. Sabbi , M. Sirianni , E. Grebel , J. Ghallager

Here, we present the 1UVA catalog of time variable ultraviolet (UV) sources. We describe a new analysis pipeline, the VAriable Source Clustering Analysis (VASCA). We apply the pipeline to 10 years of data from the GALaxy Evolution eXplorer…

Astrophysics of Galaxies · Physics 2024-07-31 Rolf Buehler , Julian Schliwinski

We report the discovery of eight X-ray sources with periodic variability in 487 ks of observations of the Galactic center with Chandra. The sources are identified from a sample of 285 objects detected with 100-4200 net counts. Their periods…

Astrophysics · Physics 2009-11-10 M. P. Muno , F. K. Baganoff , M. W. Bautz , W. N. Brandt , G. P. Garmire , G. R. Ricker , ;

In recent years several hypervelocity stars (HVSs) have been observed in the halo of our Galaxy. Such HVSs have possibly been ejected from the Galactic center and then propagated in the Galactic potential up to their current position. The…