Search Publications
Unveiling the Physical Conditions in NGC 6910
Sharma, Saurabh; Panwar, Neelam; Kaur, Harmeen +3 more
Deep and wide-field optical photometric observations along with multiwavelength archival data sets have been employed to study the physical properties of the cluster NGC 6910. The study also examines the impact of massive stars on their environment. The age, distance, and reddening of the cluster are estimated to be ∼4.5 Myr, 1.72 ± 0.08 kpc, and …
Space Telescope and Optical Reverberation Mapping Project. XI. Disk-wind Characteristics and Contributions to the Very Broad Emission Lines of NGC 5548
Brandt, W. N.; Kriss, G. A.; Mehdipour, M. +22 more
In 2014 the NGC 5548 Space Telescope and Optical Reverberation Mapping campaign discovered a two-month anomaly when variations in the absorption and emission lines decorrelated from continuum variations. During this time the soft X-ray part of the intrinsic spectrum had been strongly absorbed by a line-of-sight (LOS) obscurer, which was interprete…
Peculiarities in the Horizontal Branch Stars of Globular Cluster NGC 1851: Discovery of a Blue Straggler Companion to an EHB Star
Yadav, R. K. S.; Sahu, Snehalata; Subramaniam, Annapurni +1 more
We present a study of far-UV (FUV) bright horizontal branch (HB) stars to understand the peculiarities seen in the HB sequence of the globular cluster NGC 1851, using ground- and space-based multiwavelength data. Optical and UV color-magnitude diagrams are used to classify HB stars and their membership from Hubble Space Telescope and Gaia DR2 data…
ALMA Reveals the Molecular Gas Properties of Five Star-forming Galaxies across the Main Sequence at 3
Schinnerer, Eva; Tasca, Lidia; Liu, Daizhong +17 more
We present the detection of CO (5-4) with signal-to-noise ratio (S/N) > 7-13 and a lower CO transition with S/N > 3 (CO (4-3) for four galaxies, and CO (3-2) for one) with the Atacama Large Millimeter/submillimeter Array in bands 3 and 4 in five main-sequence (MS) star-forming galaxies with stellar masses (3-6) × 1010M⊙…
Orbital Modulation of Gamma Rays from PSR J2339-0533
An, Hongjun; Kerr, Matthew; Fermi-LAT Collaboration +1 more
We report on orbital modulation of the 100-600 MeV gamma-ray emission of the PB = 4.6 hr millisecond pulsar binary PSR J2339-0533 using 11 yr of Fermi Large Area Telescope data. The modulation has high significance (chance probability p ≈ 10-7), is approximately sinusoidal, peaks near pulsar superior conjunction, and is detec…
Flare Energy Release at the Magnetic Field Polarity Inversion Line during the M1.2 Solar Flare of 2015 March 15. II. Investigation of Photospheric Electric Current and Magnetic Field Variations Using HMI 135 s Vector Magnetograms
Zimovets, I. V.; Sharykin, I. N.; Myshyakov, I. I.
This work is a continuation of Paper I and is devoted to the analysis of nonthermal electron dynamics and plasma heating in the confined M1.2 class solar flare SOL2015-03-15T22:43, revealing energy release in the highly sheared interacting magnetic loops in the low corona, above the polarity inversion line (PIL). The aim of the present work is to …
Characterization of the Particle-induced Background of XMM-Newton EPIC-pn: Short- and Long-term Variability
Miller, Eric D.; Kraft, Ralph; Gastaldello, Fabio +16 more
The particle-induced background of X-ray observatories is produced by galactic cosmic ray (GCR) primary protons, electrons, and He ions. Events due to direct interaction with the detector are usually removed by onboard processing. The interactions of these primary particles with the detector environment produce secondary particles that mimic X-ray…
HST Survey of the Orion Nebula Cluster in the H2O 1.4 µm Absorption Band. II. The Substellar IMF Down to Planetary Masses
Gennaro, Mario; Robberto, Massimo
We utilize the ability of the Hubble Space Telescope to probe near-infrared water absorption present in the atmosphere of low-mass stars and brown-dwarf and planetary-mass objects to create a pure sample of Orion Nebula Cluster (ONC) members, not affected by contamination from background stars and galaxies that lack water absorption. Thanks to the…
OGLE-ing the Magellanic System: RR Lyrae Stars in the Bridge
Udalski, Andrzej; Mróz, Przemek; Szymański, Michał K. +12 more
We use the extended and updated Optical Gravitational Lensing Experiment (OGLE) Collection of Variable Stars to thoroughly analyze the distribution of RR Lyrae stars in the Magellanic Bridge. We use photometric metallicities to derive the absolute Wesenheit magnitude and individual distance of each RR Lyrae star. We confirm results from our earlie…
The Slow Heartbeats of an Ultraluminous X-Ray Source in NGC 3621
Salvaterra, R.; Tiengo, A.; Marelli, M. +6 more
We report on the results of X-ray observations of 4XMM J111816.0-324910, a transient ultraluminous X-ray source located in the galaxy NGC 3621. This system is characterized by a transient nature and marked variability with a characteristic timescale of ≈3500 s, in contract with other ultraluminous X-ray sources, which in the vast majority show lim…