124 citations · 611 across the 39 of their papers we have counts for
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Three New Likely Spider Millisecond Pulsar Binaries and Optical Kinematic Tracers of Intrabinary Shocks
Jay Strader, Rebecca Kyer, Laura Chomiuk +9
We report the discovery of three candidate spider millisecond pulsars via multi-wavelength follow-up of unassociated Fermi Large Area Telescope gamma-ray sources. All have optical…
A Multiwavelength Assessment Disfavoring the X-ray Binary Origin of He III Regions in Metal-Poor Star-Forming Dwarf Galaxies
Ivan Altunin, Christopher Ellis, Richard M. Plotkin +9
Recent observations of metal-poor, star-forming dwarf galaxies reveal He III regions, traced by nebular He II 4686 emission that require a strong source of extreme-ultraviolet (EUV…
New Deep Radio Continuum Imaging Still Indicates a Large Reservoir of Undiscovered Millisecond Pulsars in Terzan 5
Ryan Urquhart, Jay Strader, Laura Chomiuk +4
We present the deepest and highest-resolution radio continuum imaging of the Galactic globular cluster Terzan 5, one of the most crowded locations in the radio sky. In these new 2$…
Multiwavelength Evidence for Two New Candidate Transitional Millisecond Pulsars in the Sub-luminous Disk State: 4FGL J0639.1--8009 and 4FGL J1824.2+1231
Rebecca Kyer, Subhroja Roy, Jay Strader +4
We report the discovery of two new Galactic accreting compact objects consistent with the respective positions of the unassociated Fermi-LAT gamma-ray sources 4FGL J0639.1--8009 an…
PSR J1947-1120: A New Huntsman Millisecond Pulsar Binary
Jay Strader, Paul S. Ray, Ryan Urquhart +11
We present the discovery of PSR J1947-1120, a new huntsman millisecond pulsar with a red giant companion star in a 10.3 d orbit. This pulsar was found via optical, X-ray, and radio…
Detecting the Black Hole Candidate Population in M51's Young Massive Star Clusters: Constraints on Accreting Intermediate Mass Black Holes
Kristen C. Dage, Evangelia Tremou, Bolivia Cuevas Otahola +24
Intermediate mass black holes (10^2 < M_BH< 10^5 Msun) are an open question in our understanding of black hole evolution and growth. They have long been linked to dense star cluste…
Do Neutron Star Ultra-Luminous X-Ray Sources Masquerade as Intermediate Mass Black Holes in Radio and X-Ray?
Teresa Panurach, Kristen C. Dage, Ryan Urquhart +8
Ultraluminous X-ray sources (ULXs) were once largely believed to be powered by super-Eddington accretion onto stellar-mass black holes, although in some rare cases, ULXs also serve…
A 34 Yr Timing Solution of the Redback Millisecond Pulsar Terzan 5A
Alexandra C. Rosenthal, Scott M. Ransom, Kyle A. Corcoran +12
We present a 34-year timing solution of the redback pulsar system Terzan 5A (Ter5A). Ter5A, also known as B174424A or J17482446A, has a 11.56 ms pulse period, a 0.1 sol…
A Possible Third Body in the X-Ray System GRS 1747-312 and Models with Higher-Order Multiplicity
Caleb Painter, Rosanne Di Stefano, Vinay L. Kashyap +7
GRS 1747-312 is a bright Low-Mass X-ray Binary in the globular cluster Terzan 6, located at a distance of 9.5 kpc from the Earth. It exhibits regular outbursts approximately every…
Discovery of An X-ray Photoionized Optical Nebula and A Radio Nebula Associated with the ULX NGC 4861 X-1
Hang Gong, Ryan Urquhart, Alexandr Vinokurov +5
We have conducted long-slit spectroscopic observations and analyzed archival radio data for the ultraluminous X-ray source (ULX) NGC 4861 X-1. Our spectral line analysis unveils th…
Catching a nova X-ray/UV flash in the visible? Early spectroscopy of the extremely slow Nova Velorum 2022 (Gaia22alz)
E. Aydi, L. Chomiuk, J. Mikołajewska +22
We present early spectral observations of the very slow Galactic nova Gaia22alz, over its gradual rise to peak brightness that lasted 180 days. During the first 50 days, when the n…
Tracking the Enigmatic Globular Cluster Ultracompact X-ray Binary X1850--087: Extreme Radio Variability in the Hard State
T. Panurach, R. Urquhart, J. Strader +6
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…
Multiwavelength Scrutiny of X-ray Sources in Dwarf Galaxies: ULXs versus AGN
Erica Thygesen, Richard M. Plotkin, Roberto Soria +10
Owing to their quiet evolutionary histories, nearby dwarf galaxies (stellar masses ) have the potential to teach us about the mechanism(s) t…
Quasi periodic whispers from a transient ULX in M\,101: signatures of a fast-spinning neutron star?
Ryan T. Urquhart, Roberto Soria, Rosanne Di Stefano +7
We have studied the unusual time variability of an ultraluminous X-ray source in M 101, 4XMM J140314.2541806 (henceforth, J1403), using Chandra and XMM-Newton data. Over the las…
The MAVERIC Survey: Variable Jet-Accretion Coupling in Luminous Accreting Neutron Stars in Galactic Globular Clusters
T. Panurach, J. Strader, A. Bahramian +9
Accreting neutron stars in low-mass X-ray binaries show outflows -- and sometimes jets -- in the general manner of accreting black holes. However, the quantitative link between the…
Ultraluminous X-ray Sources in Seven Edge-On Spiral Galaxies
Kristen C. Dage, Noah Vowell, Erica Thygesen +8
We investigate a sample of seven edge-on spiral galaxies using Chandra observations. Edge-on spiral galaxies allow us to clearly separate source associated with their star-forming…
Classical Novae at Radio Wavelengths
Laura Chomiuk, Justin D. Linford, Elias Aydi +20
We present radio observations (1--40 GHz) for 36 classical novae, representing data from over five decades compiled from the literature, telescope archives, and our own programs. O…
Multiwavelength evidence for a new flare-mode transitional millisecond pulsar
Jay Strader, Samuel J. Swihart, Ryan Urquhart +7
We report the discovery of a new low-mass X-ray binary near the center of the unassociated Fermi GeV gamma-ray source 4FGL J0540.0-7552. The source shows the persistent presence of…
The ultraluminous X-ray source bubble in NGC 5585
Roberto Soria, Manfred Pakull, Christian Motch +4
Some ultraluminous X-ray sources (ULXs) are surrounded by collisionally ionized bubbles, larger and more energetic than supernova remnants: they are evidence of the powerful outflo…
A New Candidate Transitional Millisecond Pulsar in the Sub-luminous Disk State: 4FGL J0407.7--5702
Jessie M. Miller, Samuel J. Swihart, Jay Strader +7
We report the discovery of a variable optical and X-ray source within the error ellipse of the previously unassociated Fermi Large Area Telescope -ray source 4FGL J0407.7--5702.…
M51-ULS-1b: The First Candidate for a Planet in an External Galaxy
R. Di Stefano, Julia Berndtsson, Ryan Urquhart +4
Do external galaxies host planetary systems? Many lines of reasoning suggest that the answer must be 'yes'. In the foreseeable future, however, the question cannot be answered by t…
The MAVERIC Survey: New compact binaries revealed by deep radio continuum observations of the Galactic globular cluster Terzan 5
Ryan Urquhart, Arash Bahramian, Jay Strader +12
Owing to its massive, dense core, Terzan 5 has the richest population of millisecond pulsars known among Galactic globular clusters. Here we report new deep GHz radio contin…
GS 2000+25: The Least Luminous Black Hole X-ray Binary
J. Rodriguez, R. Urquhart, R. M. Plotkin +6
Little is known about the properties of the accretion flows and jets of the lowest-luminosity quiescent black holes. We report new, strictly simultaneous radio and X-ray observatio…
A New Likely Redback Millisecond Pulsar Binary with a Massive Neutron Star: 4FGL J2333.1--5527
Samuel J. Swihart, Jay Strader, Ryan Urquhart +7
We present the discovery of a likely new redback millisecond pulsar binary associated with the \emph{Fermi} -ray source 4FGL J2333.1--5527. Using optical photometric and spectro…