Search Publications
An Unusual Reservoir of Water Emission in the VV CrA A Protoplanetary Disk
Pascucci, Ilaria; Banzatti, Andrea; Carmona, Andrés +7 more
We present an analysis of an unusual pattern of water vapor emission from the ~2 Myr old low-mass binary system VV CrA, as observed in IR spectra obtained with VLT-CRIRES, VLT-VISIR, and Spitzer-IRS. Each component of the binary shows emission from water vapor in both the L (~3 µm) and N (~12 µm) bands. The N-band and Spitzer spectra a…
Investigating a predicted metallicity [Fe/H] variation in the Type II Globular Cluster NGC 362
Sarajedini, Ata; Monaco, L.; Geisler, D. +4 more
NGC 362 is a non-common Type II Galactic globular cluster, showing a complex pseudo two-colour diagram or 'chromosome map'. The clear separation of its stellar populations in the colour-magnitude diagram and the distribution of the giant stars in the chromosome map strongly suggests that NGC 362 could host stars with both cluster-nominal, as well …
Spatially Resolved X-Ray Study of Supernova Remnant G306.3-0.9 with Unusually High Calcium Abundance
Toonen, Silvia; Nomoto, Ken'ichi; Vink, Jacco +6 more
G306.3-0.9 is an asymmetric Galactic supernova remnant (SNR), whose progenitor has been thought to be a Type Ia supernova (SN), but its high Ca abundance appears inconsistent with the Type Ia origin. Hoping to uncover the reason for its asymmetry and the origin of this SNR, we performed a spatially resolved X-ray spectroscopic analysis of XMM-Newt…
The missing radial velocities of Gaia: Blind predictions for DR3
Widmark, Axel; Naik, Aneesh P.
While Gaia has observed the phase space coordinates of over a billion stars in the Galaxy, in the overwhelming majority of cases it has only obtained five of the six coordinates, the missing dimension being the radial (line-of-sight) velocity. Using a realistic mock data set, we show that Bayesian neural networks are highly capable of 'learning' t…
Doppler shifts of spectral lines formed in the solar transition region and corona
Chen, Yajie; Tian, Hui; Peter, Hardi +2 more
Context. Emission lines formed in the transition region and corona dominantly show redshifts and blueshifts, respectively.
Aims: We investigate the Doppler shifts in a 3D radiation magnetohydrodynamic (MHD) model of the quiet Sun and compare these to observed properties. We concentrate on Si IV 1394 Å originating in the transition region and …
Counterparts of candidate dusty starbursts at z > 6
Yan, Haojing; Ling, Chenxiaoji; Ma, Zhiyuan
We present an analysis of the optical-to-near-infrared (IR) counterparts of a sample of candidate dusty starbursts at z > 6. These objects were pre-selected based on the rising trend of their far-IR-to-sub-millimeter spectral energy distributions and the fact that they are radio-weak. Their precise positions are available through millimeter and…
A search for period changes of eight short-period Type II Cepheids
Whitelock, Patricia A.; Kniazev, Alexei Y.; Yacob, Alemiye M. +2 more
In this study, we investigate the period changes of eight short-period Type II Cepheids of the BL Her subtype, i.e. with periods in the 1-4 d range. The O - C diagrams for these stars are constructed using all suitable observational data from ground and space surveys. This spans a time interval of over one century and includes digitized photograph…
Search for Hα Emitters at z 7.8: A Constraint on the Hα-based Star Formation Rate Density
Asada, Yoshihisa; Ohta, Kouji
We search for Hα emitters at z ~ 7.8 in four gravitationally lensed fields observed in the Hubble Frontier Fields program. We use the Lyman break method to select galaxies at the target redshift and perform photometry in the Spitzer/IRAC 5.8 µm band to detect Hα emission from the candidate galaxies. We find no significant detections of count…
Use of Twenty Years CLUSTER/FGM Data to Observe the Mean Behavior of the Magnetic Field and Current Density of Earth's Magnetosphere
Dunlop, M. W.; Robert, P.
The data from the CLUSTER FGM magnetometer, recorded for 20 years at ESA's Cluster Science Archive, as well as the position of the spacecraft, have been used to form a database aligned in time. It allows the calculation of curl(B) over all the lifetime of the mission (representing the current density via µ0J⃗=curl⃗>(B⃗>). The B⃗…
Megashears and hydrothermalism at the Martian crustal dichotomy in Valles Marineris
Langlais, Benoit; Mège, Daniel; Gurgurewicz, Joanna +2 more
Observations of ancient deep deformation systems on Mars are important for constraining planetary dynamics, as well as to identify potential mineral resources. However, such systems were thought to be unexposed and inaccessible to analysis. Here, we apply structural and hyperspectral analyses, and correlate results with magnetic anomaly patterns, …