Search Publications
Constraining planetary albedo of JWST targets in the TESS bandpass, using TESS, HST, and Spitzer eclipse depth observations
Goyal, Jayesh; Arora, Rahul
Albedo is one of the important characteristics of hot Jupiter exoplanets. However, albedo constraints have been obtained for very few exoplanets. In this work, we present the Transiting Exoplanet Survey Satellite (TESS) phase curve observations of WASP-18b, WASP-19b, WASP-121b, WASP-43b, WASP-17b, and WASP-77b, all targets for atmospheric characte…
DanceCam: atmospheric turbulence mitigation in wide-field astronomical images with short-exposure video streams
Cuillandre, Jean-Charles; Bialek, Spencer; Bertin, Emmanuel +4 more
We introduce a novel technique to mitigate the adverse effects of atmospheric turbulence on astronomical imaging. Utilizing a video-to-image neural network trained on simulated data, our method processes a sliding sequence of short-exposure (~0.2 s) stellar field images to reconstruct an image devoid of both turbulence and noise. We demonstrate th…
Validation of up to seven TESS planet candidates through multi-colour transit photometry using MuSCAT2 data
Tamura, M.; Pallé, E.; Béjar, V. J. S. +62 more
The TESS mission searches for transiting exoplanets by monitoring the brightness of hundreds of thousands of stars across the entire sky. M-type planet hosts are ideal targets for this mission due to their smaller size and cooler temperatures, which makes it easier to detect smaller planets near or within their habitable zones. Additionally, M dwa…
Atomic Transition Probabilities for Ultraviolet and Optical Lines of Tm II
Roederer, I. U.; Den Hartog, E. A.; Voith, G. T.
We report new branching fraction measurements for 224 ultraviolet and optical transitions of Tm II. These transitions range in wavelength (wavenumber) from 2350 to 6417 Å (42,532–15,579 cm‑1) and originate in 13 odd-parity and 24 even-parity upper levels. Thirty-five of the 37 levels, accounting for 213 of the 224 transitions, are studi…
Molecular Hydrogen Line Identifications in Solar Flares Observed by IRIS: Lower Atmospheric Structure from Radiometric Analysis
Jaeggli, Sarah A.; Daw, Adrian N.
A rich spectrum of molecular hydrogen (H2) emission lines is seen in sensitive observations from the far-ultraviolet (FUV) channels of the Interface Region Imaging Spectrograph (IRIS) during flare activity in solar active region NOAA Active Region 11861. Based on this observation, we have determined 37 new line identifications by compar…
SuperBIT Superpressure Flight Instrument Overview and Performance: Near-diffraction-limited Astronomical Imaging from the Stratosphere
Massey, Richard; Jauzac, Mathilde; Harvey, David +26 more
SuperBIT was a 0.5 m near-UV to near-infrared wide-field telescope that launched on a NASA superpressure balloon into the stratosphere from New Zealand for a 45-night flight. SuperBIT acquired multiband images of galaxy clusters to study the properties of dark matter using weak gravitational lensing. We provide an overview of the instrument and it…
Spectro-photometric follow-up of the outbursting AM CVn system ASASSN-21br
Mukai, K.; Maccarone, T. J.; Kochanek, C. S. +8 more
We report on spectroscopic and photometric observations of the AM Canum Venaticorum (AM CVn) system ASASSN-21br, which was discovered in outburst by the All-Sky Automated Survey for Supernovae in 2021 February. The outburst lasted for around three weeks, and exhibited a pronounced brightness dip for $\approx$4 d, during which the spectra showed a …
Lifetime of starspots on detached eclipsing binaries: Detecting the effects of tides on stellar activity
Zong, Weikai; Wang, Jiaxin; Pan, Yang +5 more
Context. Tidal deformation breaks the axisymmetric structure of stars, and this may affect stellar activity. This effect has been demonstrated in theoretical analyses and simulations, but it lacks observational support. In this paper, we use spot-modulated detached binaries to study the effect of tides on stellar activity. We show this effect by a…
Rotational Velocities and Radii Estimates of Low-mass Pre-main-sequence Stars in NGC 2264
Rhode, Katherine L.; Rebull, Luisa M.; Gray, Laurin M. +2 more
Investigating the angular momentum evolution of pre-main-sequence (PMS) stars provides important insight into the interactions between Sun-like stars and their protoplanetary disks, and the timescales that govern disk dissipation and planet formation. We present projected rotational velocities (v sin i values) of 254 T Tauri stars (TTSs) in the ∼3…
Dark matter search in the Perseus cluster with simultaneous analysis of Hitomi and Suzaku data
Kitamoto, Shunji; Sawada, Makoto; Tamura, Takayuki +1 more
The reported detection of a 3.5 keV emission line in the Perseus cluster, possibly originating from dark matter decay, is still under scrutiny. Despite extensive observations, the detection has not yet been confirmed, and its origin remains a topic of active debate. Most of the previous searches relied on spectroscopy with X-ray charge-coupled dev…