Search Publications
Active Galactic Nuclei in the Green Valley at z ∼ 0.7
Ji, Zhiyuan; Rieke, Marcia; Williams, Christina C. +5 more
We present near-infrared (NIR) spectroscopy using the MMT and Magellan infrared spectrograph for a sample of 29 massive galaxies (
An analysis of spectroscopic, seismological, astrometric, and photometric masses of pulsating white dwarf stars
Kepler, S. O.; Córsico, Alejandro H.; Uzundag, Murat +3 more
Context. A central challenge in the field of stellar astrophysics lies in accurately determining the mass of stars, particularly when dealing with isolated ones. However, for pulsating white dwarf stars, the task becomes more tractable due to the availability of multiple approaches such as spectroscopy, asteroseismology, astrometry, and photometry…
A Statistical Study of Magnetic Flux Emergence in Solar Active Regions Prior to Strongest Flares
Abramenko, Valentina I.; Kutsenko, Alexander S.; Plotnikov, Andrei A.
Using the data on magnetic field maps and continuum intensity for Solar Cycles 23 and 24, we explored 100 active regions (ARs) that produced M5.0 or stronger flares. We focus on the presence/absence of the emergence of magnetic flux in these ARs 2–3 days before the strong flare onset. We found that 29 ARs in the sample emerged monotonically amidst…
TESSILATOR: a one-stop shop for measuring TESS rotation periods
Günther, H. M.; Binks, A. S.
We present a software package designed to produce photometric light curves and measure rotation periods from full-frame images taken by the Transiting Exoplanet Survey Satellite (TESS), which we name 'TESSILATOR'. TESSILATOR is the only publicly available code that will run a full light curve and rotation period ($P_{\rm rot}$) analysis based on j…
Ongoing and Fossil Large-scale Outflows Detected in a High-redshift Radio Galaxy: [C II] Observations of TN J0924-2201 at z = 5.174
Imanishi, Masatoshi; Kohno, Kotaro; Schramm, Malte +13 more
We present Atacama Large Millimeter/submillimeter Array observations of the [C II] 158 µm line and the underlying continuum emission of TN J0924‑2201, which is one of the most distant known radio galaxies at z > 5. The [C II] line and 1 mm continuum emission are detected at the host galaxy. The systemic redshift derived from the [C II] li…
Europa's H2O2: Temperature Insensitivity and a Correlation with CO2
Brown, Michael E.; de Kleer, Katherine; Trumbo, Samantha K. +1 more
H2O2 is part of Europa's water-ice radiolytic cycle and a potential source of oxidants to Europa's subsurface ocean. However, factors controlling the concentration of this critical surface species remain unclear. Though laboratory experiments suggest that Europa's H2O2 should be concentrated in the colde…
A model of light pseudoscalar dark matter
Chakdar, Shreyashi; Ghosh, Dilip Kumar; Hung, P. Q. +2 more
The EW-
A Hot Core in the Group-dominant Elliptical Galaxy NGC 777
Babul, Arif; David, Laurence P.; O'Sullivan, Ewan +8 more
NGC 777 provides an example of a phenomenon observed in some group-central ellipticals, in which the temperature profile shows a central peak, despite the short central cooling time of the intragroup medium. We use deep Chandra X-ray observations of the galaxy, supported by uGMRT 400 MHz radio imaging, to investigate the origin of this hot core. W…
Toward a Live Homogeneous Database of Solar Active Regions Based on SOHO/MDI and SDO/HMI Synoptic Magnetograms. II. Parameters for Solar Cycle Variability
Wang, Ruihui; Jiang, Jie; Luo, Yukun
Solar active regions (ARs) determine solar polar fields and cause solar cycle variability within the framework of the Babcock–Leighton dynamo. The contribution of an AR to the polar field is measured by its dipole field, which results from flux emergence and subsequent flux transport over the solar surface. The dipole fields contributed by an AR b…
VLBI detection of the AE Aqr twin, LAMOST J024048.51+195226.9
Zhang, Bo; Yang, Jun; An, Tao +8 more
LAMOST J024048.51+195226.9 (J0240+1952) was recently identified as the second AE Aquarii (AE Aqr)-type cataclysmic variable, possessing the fastest known rotating white dwarf. We performed a Very Long Baseline Interferometry (VLBI) observation of J0240+1952 utilizing the European VLBI Network at 1.7 GHz, to obtain the first view of the radio morph…