Search Publications
Dusty wind of W Hydrae. Multi-wavelength modelling of the present-day and recent mass loss
Waters, L. B. F. M.; de Koter, A.; Decin, L. +5 more
Context. Low- and intermediate-mass stars go through a period of intense mass-loss at the end of their lives, during the asymptotic giant branch (AGB) phase. While on the AGB a significant part, or even most, of their initial mass is expelled in a stellar wind. This process controls the final stages of the evolution of these stars and contributes …
Probing gravity at large scales through CMB lensing
Ho, Shirley; Alam, Shadab; Pullen, Anthony R.
We describe a methodology to probe gravity with the cosmic microwave background (CMB) lensing convergence κ, specifically by measuring EG, the ratio of the Laplacian of the gravitational scalar potential difference to the velocity divergence. Using CMB lensing instead of galaxy-galaxy lensing avoids intrinsic alignments while also lacki…
Propagating Disturbances in the Solar Corona and Spicular Connection
Pant, Vaibhav; Banerjee, Dipankar; Samanta, Tanmoy
Spicules are small, hairy-like structures seen at the solar limb, mainly at chromospheric and transition region lines. They generally live for 3-10 minutes. We study these spicules in a south polar region of the Sun with coordinated observations using the Interface Region Imaging Spectrograph (IRIS) and the Atmospheric Imaging Assembly (AIA) instr…
First measurement of H I 21 cm emission from a GRB host galaxy indicates a post-merger system
Kanekar, Nissim; Michałowski, Michał J.; Roychowdhury, Sambit +2 more
We report the detection and mapping of atomic hydrogen in H I 21 cm emission from ESO 184-G82, the host galaxy of the gamma-ray burst 980425. This is the first instance where H I in emission has been detected from a galaxy hosting a gamma-ray burst (GRB). ESO 184-G82 is an isolated galaxy and contains a Wolf-Rayet region close to the location of t…
Mg II Lines Observed During the X-class Flare on 29 March 2014 by the Interface Region Imaging Spectrograph
Heinzel, P.; Liu, W.; Kleint, L. +1 more
Mg II lines represent one of the strongest emissions from the chromospheric plasma during solar flares. In this article, we studied the Mg II lines observed during the X1 flare on 29 March 2014 (SOL2014-03-29T17:48) by the Interface Region Imaging Spectrograph (IRIS). IRIS detected large intensity enhancements of the Mg II h and k lines, subordina…
The AKARI 2.5-5.0 µm Spectral Atlas of Type-1 Active Galactic Nuclei: Black Hole Mass Estimator, Line Ratio, and Hot Dust Temperature
Nakagawa, Takao; Oyabu, Shinki; Ohyama, Youichi +11 more
We present 2.5-5.0 µm spectra of 83 nearby (0.002 < z < 0.48) and bright (K < 14 mag) type-1 active galactic nuclei (AGNs) taken with the Infrared Camera on board AKARI. The 2.5-5.0 µm spectral region contains emission lines such as Brβ (2.63 µm), Brα (4.05 µm), and polycyclic aromatic hydrocarbons (3.3 µm), …
Episodic Ejection from Active Asteroid 311P/PANSTARRS
Mutchler, Max; Jewitt, David; Agarwal, Jessica +2 more
We examine the development of the active asteroid 311P/PANSTARRS (formerly, 2013 P5) in the period from 2013 September to 2014 February using high resolution images from the Hubble Space Telescope. This multi-tailed object is characterized by a single, reddish nucleus of absolute magnitude H >= 18.98 ± 0.10, corresponding to an equal-area spher…
Submillimeter mapping of mesospheric minor species on Venus with ALMA
Lellouch, E.; Encrenaz, T.; Moreno, R. +2 more
Millimeter and submillimeter heterodyne spectroscopy offers the possibility of probing the mesosphere of Venus and monitoring minor species and winds. ALMA presents a unique opportunity to map mesospheric species of Venus. During Cycle 0, we have observed Venus on November 14 and 15, 2011, using the compact configuration of ALMA. The diameter of V…
Cloud structure and composition of Jupiter's troposphere from 5- µ m Cassini VIMS spectroscopy
Fletcher, L. N.; Irwin, P. G. J.; Giles, R. S.
Jupiter's tropospheric composition and cloud structure are studied using Cassini VIMS 4.5-5.1 µ m thermal emission spectra from the 2000-2001 flyby. We make use of both nadir and limb darkening observations on the planet's nightside, and compare these with dayside observations. Although there is significant spatial variability in the 5- &mic…
XMM-Newton Observations of SGR 1806-20 Over Seven Years Following the 2004 Giant Flare
Kouveliotou, C.; Kaspi, V. M.; Younes, G.
We report on the study of 14 XMM-Newton observations of the magnetar SGR 1806-20 spread over a period of 8 years, starting in 2003 and extending to 2011. We find that in mid 2005, a year and a half after a giant flare (GF), the torques on the star increased to the largest value yet seen, with a long term average rate between 2005 and 2011 of | \do…