36 hasil untuk "Jay Strader"
Menampilkan 1–20 · 0,37 detik · RSS
-
Artikel Jurnal Teks lengkap
Intermediate-Mass Black Holes
We describe ongoing searches for intermediate-mass black holes with M BH ≈ 10–10 5 M ⊙ . We review a range of search mechanisms, both dynamical and those that rely on accretion signatures. We find the following conclusions: ▪ Dynamical and accretion signatures alike point to a high fraction of 10 9…
-
Artikel Jurnal
Multiwavelength Evidence for Two New Candidate Transitional Millisecond Pulsars in the Subluminous Disk State: 4FGL J0639.1-8009 and 4FGL J1824.2+1231
We report the discovery of two new Galactic accreting compact objects consistent with the respective positions of the unassociated Fermi-LAT γ -ray sources 4FGL J0639.1-8009 and 4FGL J1824.2+1231. A combination of new and archival X-ray data from Chandra, XMM-Newton, Swift/XRT, and eROSITA reveals…
-
Artikel Jurnal
The Binary Properties of Stellar Streams Are Set by Cluster Dynamics
We present a suite of direct N -body simulations of low-mass (
-
Artikel Jurnal
Constraints on the z ∼ 5 Star-forming Galaxy Luminosity Function From Hubble Space Telescope Imaging of an Unbiased and Complete Sample of Long Gamma-Ray Burst Host Galaxies
We present rest-frame UV Hubble Space Telescope imaging of the largest and most complete sample of 23 long-duration gamma-ray burst (GRB) host galaxies between redshifts 4 and 6. Of these 23, we present new WFC3/F110W imaging for 19 of the hosts, which we combine with archival WFC3/F110W and…
-
Artikel Jurnal
A Contact Binary Misclassified as an Ellipsoidal Variable: Complications for Detached Black Hole Searches
Identifying sources exhibiting ellipsoidal variability in large photometric surveys is becoming a promising method to search for candidate detached black holes (BHs) in binaries. This technique aims to exploit the orbital-phase-dependent modulation in optical photometry caused by the BH distorting…
-
Artikel Jurnal
Is the M81 Fast Radio Burst Host Globular Cluster Special?
We use multiband archival Hubble Space Telescope (HST) observations to measure the photometric and structural parameters of the M81 globular cluster (GC) that hosts the fast radio burst FRB 20200120E. Our best-fitting King model has an effective radius r _h = 3.06 pc with a moderate King model…
-
Artikel Jurnal
Metallicity Mapping of the Ionized Diffuse Gas at the Milky Way Disk–Halo Interface
Metals in the diffuse, ionized gas at the boundary between the Milky Way’s interstellar medium (ISM) and circumgalactic medium, known as the disk–halo interface (DHI), are valuable tracers of the feedback processes that drive the Galactic fountain. However, metallicity measurements in this region…
-
Artikel Jurnal
No Evidence for Accretion around the Intermediate-mass Black Hole in Omega Centauri
For over a decade, both theoretical predictions and observational studies have suggested that ω Centauri ( ω Cen), the most massive Milky Way globular cluster, might harbor an intermediate-mass black hole (IMBH). Recently, identification of fast-moving stars in the core of ω Cen provided the…
-
Artikel Jurnal
X-Ray Constraints on Wandering Black Holes in Stripped Galaxy Nuclei in the Halo of NGC 5128
A subset of galaxies have dense nuclei, and when these galaxies are accreted and tidally stripped, the nuclei can masquerade as globular clusters in the halos of large galaxies. If these nuclei contain massive central black holes, some may accrete gas and become observable as active galactic…
-
Artikel Jurnal
Tracking the Enigmatic Globular Cluster Ultracompact X-Ray Binary X1850–087: Extreme Radio Variability in the Hard State
The conditions under which accreting neutron stars launch radio-emitting jets and/or outflows are still poorly understood. The ultracompact X-ray binary X1850–087, located in the globular cluster NGC 6712, is a persistent atoll-type X-ray source that has previously shown unusual radio-continuum…
-
Artikel Jurnal
Pavo: Discovery of a Star-forming Dwarf Galaxy Just Outside the Local Group
We report the discovery of Pavo, a faint ( M _V = −10.0), star-forming, irregular, and extremely isolated dwarf galaxy at D ≈ 2 Mpc. Pavo was identified in Dark Energy Camera Legacy Survey imaging via a novel approach that combines low surface brightness galaxy search algorithms and…
-
Artikel Jurnal
Corvus A: A Low-mass, Isolated Galaxy at 3.5 Mpc
We report the discovery of Corvus A, a low-mass, gas-rich galaxy at a distance of approximately 3.5 Mpc, identified in DR10 of the Dark Energy Camera Legacy Imaging Survey during the initial phase of our ongoing SEmi-Automated Machine LEarning Search for Semi-resolved galaxies (SEAMLESS). Jansky…
-
Artikel Jurnal
New Velocity Measurements of NGC 5128 Globular Clusters Out to 130 kpc: Outer Halo Kinematics, Substructure, and Dynamics
We present new radial velocity measurements from the Magellan and the Anglo-Australian Telescopes for 175 previously known and 121 newly confirmed globular clusters (GCs) around NGC 5128, the nearest accessible massive early-type galaxy at D = 3.8 Mpc. Remarkably, 28 of these newly confirmed GCs…
-
Artikel Jurnal
Ultradeep ATCA Imaging of 47 Tucanae Reveals a Central Compact Radio Source
We present the results of an ultradeep radio continuum survey, containing ∼480 hr of observations, of the Galactic globular cluster 47 Tucanae with the Australia Telescope Compact Array. This comprehensive coverage of the cluster allows us to reach rms noise levels of 1.19 μ Jy beam ^−1 at 5.5 GHz…
-
Artikel Jurnal
Multiwavelength Observations of a New Redback Millisecond Pulsar 4FGL J1910.7−5320
We present the study of multiwavelength observations of an unidentified Fermi Large Area Telescope (LAT) source, 4FGL J1910.7−5320, a new candidate redback millisecond pulsar binary. In the 4FGL 95% error region of 4FGL J1910.7−5320, we find a possible binary with a 8.36 hr orbital period from the…
-
Artikel Jurnal
A 2.9 hr Periodic Radio Transient with an Optical Counterpart
We present a long-period radio transient (GLEAM-X J0704−37) discovered to have an optical counterpart, consistent with a cool main-sequence star of spectral type M3. The radio periodicity occurs at the longest period yet found, 2.9 hr, and was discovered in archival low-frequency data from the…
-
Artikel Jurnal
The Faint Satellite System of NGC 253: Insights into Low-density Environments and No Satellite Plane
We have conducted a systematic search around the Milky Way (MW) analog NGC 253 ( D = 3.5 Mpc), as a part of the Panoramic Imaging Survey of Centaurus and Sculptor (PISCeS)—a Magellan+Megacam survey to identify dwarfs and other substructures in resolved stellar light around MW-mass galaxies outside…
-
Artikel Jurnal
PSR J1947−1120: A New Huntsman Millisecond Pulsar Binary
We present the discovery of PSR J1947–1120, a new huntsman millisecond pulsar with a red giant companion star in a 10.3 day orbit. This pulsar was found via optical, X-ray, and radio follow-up of the previously unassociated γ -ray source 4FGL J1947.6–1121. PSR J1947–1120 is the second confirmed…
-
Artikel Jurnal
A Census of Dwarf Galaxy Satellites around LMC-mass Galaxy NGC 2403
We present the first comprehensive census of the satellite population around a Large Magellanic Cloud stellar-mass galaxy, as part of the Magellanic Analog Dwarf Companions and Stellar Halos (MADCASH) survey. We have surveyed NGC 2403 ( D = 3.0 Mpc) with the Subaru/Hyper Suprime-Cam imager out to a…
-
Artikel Jurnal
A Long Period Stellar-mass Black Hole Binary in ω Centauri
Modern simulations of stellar dynamics in globular clusters peg a dominant role for stellar-mass black holes, but direct evidence for black holes in clusters remains limited. We present the discovery of an astrometric stellar-mass black hole–main sequence star binary in ω Centauri, the most massive…