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Related papers: Digging deeper into the dense Galactic globular cl…

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Globular clusters (GCs) are established emitters of high-energy (HE, 100 MeV<E<100 GeV) \gamma-ray radiation which could originate from the cumulative emission of the numerous millisecond pulsars (msPSRs) in the clusters' cores or from…

High Energy Astrophysical Phenomena · Physics 2019-08-14 P. Eger , C. van Eldik

We obtained a series of more than two hundred R-band CCD images for the crowded central (115"x77") region of the metal-poor globular cluster M15 with an angular resolution of 0.5"-0.9" in most images. Optimal image subtraction was used to…

Astrophysics · Physics 2009-11-10 Alexander P. Zheleznyak , Valery V. Kravtsov

We present $V$-band light curves of 61 variables from the core of the globular cluster M5 obtained using a newly developed image subtraction method (ISM). Four of these variables were previously unknown. Only 26 variables were found in the…

Astrophysics · Physics 2009-10-31 A. Olech , P. R. Wozniak , C. Alard , J. Kaluzny , I. B. Thompson

We have conducted a deep photometric survey of a 0.5 deg x 0.5 deg area of the Galactic Plane using the WFI instrument on the 2.2-m ESO telescope on La Silla, Chile. The dataset comprises a total of 267 R-band images, 204 from a 16 day…

Solar and Stellar Astrophysics · Physics 2015-05-19 V. R. Miller , M. D. Albrow , C. Afonso , Th. Henning

We have used DOLORES at the TNG to obtain B,V time series photometry of NGC 2419, one of the most distant and bright clusters in the Galactic halo. These data will be used to study its variable star population in order to check whether the…

We have obtained deep multifrequency radio observations of seven globular clusters using the Very Large Array and the Australia Telescope Compact Array. Five of these, NGC 6440, NGC 6539, NGC 6544, NGC 6624 and Terzan 5 had previously been…

Astrophysics · Physics 2009-10-31 A. S. Fruchter , W. M. Goss

The James Webb Space Telescope provides an exciting opportunity to investigate stellar systems located in heavily obscured regions like the Galactic bulge. Possibly, the most enigmatic among them is Terzan 5: long classified as a globular…

A search for variable stars in the globular cluster NGC 288 was carried out using a time-series of CCD images in the $V$ and $I$ filters. The photometry of all stellar sources in the field of view of our images, down to $V\approx19$ mag,…

Solar and Stellar Astrophysics · Physics 2014-01-23 A. Arellano Ferro , D. M. Bramich , S. Giridhar , R. Figuera Jaimes , N. Kains , K. Kuppuswamy

We present the commissioning results and first scientific observations from the newly installed TWIST observatory - a 50 cm telescope equipped with an sCMOS camera providing a $36.1\times24.1$ arcmin$^2$ field of view - housed in the former…

Transitional millisecond pulsars are accreting millisecond pulsars that switch between accreting X-ray binary and millisecond radio pulsar states. Only a handful of these objects have been identified so far. Terzan 5 CX1 is a variable hard…

GRS 1747-312 is a bright transient X-ray source in the globular cluster Terzan 6 with quasi-periodic outbursts approximately every 4.5 months. We carried out 2-60 keV target-of-opportunity observations during eight outbursts with the…

We present new time-series CCD photometry, in the B and V bands, for the moderately metal-rich ([Fe/H] ~ -1.3) Galactic globular cluster (GC) M62 (NGC 6266). The present dataset is the largest obtained so far for this cluster, and consists…

Solar and Stellar Astrophysics · Physics 2015-05-20 R. Contreras , M. Catelan , H. A. Smith , B. J. Pritzl , J. Borissova , C. A. Kuehn

We report the discovery of a variable blue straggler in the core of the globular cluster M5, based on a 12-hour long series of images obtained with the Planetary Camera aboard the Hubble Space Telescope. In addition, we present the light…

Astrophysics · Physics 2009-10-30 L. Drissen , M. M. Shara

We have discovered 21 millisecond pulsars (MSPs) in the globular cluster Terzan 5 using the Green Bank Telescope, bringing the total of known MSPs in Terzan 5 to 24. These discoveries confirm fundamental predictions of globular cluster and…

We present a ground-based time-series photometric study of stellar variability in four intermediate- to old-age open clusters NGC 2192, NGC 2266, NGC 2509, and IC 1369 based on high-cadence Cousins R-band observations obtained with the 0.6…

Solar and Stellar Astrophysics · Physics 2026-03-17 K. Belwal , D. Bisht , Ing-Guey Jiang , Mohit Singh Bisht , A. Raj , S. K. Chakrabarti , D. Bhowmick

Containing the oldest stars in the Galaxy, globular clusters toward the bulge can be used to trace its dynamical and chemical evolution. In the bulge direction, there are ~50 clusters, but only about 20% have been subject of high-resolution…

Solar and Stellar Astrophysics · Physics 2015-06-23 E. Valenti , L. Origlia , A. Mucciarelli , R. M. Rich

We present the results of a photometric search for variable stars in the core of the Galactic globular cluster M4. The input data are a large and unprecedented set of deep Hubble Space Telescope WFC3 images (large program GO-12911; 120…

We present the results of a commissioning campaign to observe Galactic globular clusters for the search of microlensing events. The central 10' X 10' region of the globular cluster NGC 5024 was monitored using the 2-m Himalayan Chandra…

Astrophysics of Galaxies · Physics 2015-05-28 M. Safonova , C. S. Stalin

Cosmic rays travelling through interstellar space have their propagation directions repeatedly scattered by fluctuating interstellar magnetic fields. The nature of this scattering is a major unsolved problem in astrophysics, one that has…

High Energy Astrophysical Phenomena · Physics 2024-06-27 Mark R. Krumholz , Roland M. Crocker , Arash Bahramian , Pol Bordas