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Independent study and spectral classification of a sample of poorly studied high proper motion M-dwarf candidate stars
Merc, J.; Csörnyei, G.; Cabello, C. +2 more
We report an independent spectral classification of a sample of poorly studied M-dwarf candidate stars observed with the OSIRIS instrument at GTC. Our project was carried out as an independent test of the spectral classification. It is crucial for the studies of extrasolar planets orbiting M-dwarfs, since properties of the host star are directly r…
XMM-Newton and Chandra Observations of the Unidentified Fermi-LAT Source 3FGL J1016.5-6034: A Young Pulsar with a Nebula?
Kargaltsev, Oleg; Younes, George; Hare, Jeremy +2 more
We report the discovery of a bright X-ray source in the XMM-Newton and Chandra X-Ray Observatory (Chandra) images of the unidentified Fermi-LAT source 3FGL J1016.5-6034. The XMM-Newton spectrum of the source is well fit by an absorbed blackbody+power-law model with a temperature kT = 0.20 ± 0.02 keV and photon index Γ = 1.8 ± 0.1. Chandra resolves…
Characterization of the Agilkia region through discrete-element simulation of Philae's rebound
Grieger, Björn; Küppers, Michael; Wu, Xiaoyu +1 more
Context. The cold gas system and anchoring harpoons that were designed to hold Philae down after it landed on the Agilkia region of comet 67P/Churyumov-Gerasimenko (67P) failed. This caused the lander to move on a complex trajectory that comprised multiple impacts and rebounds. The motion of Philae was mainly dominated by the gravitational environ…
Pushing Automated Abundance Derivations into the Cool Dwarf Regime: A Test Using Three G and Two K Stars in Praesepe
Hawkins, Keith; Agüeros, Marcel A.; Schuler, Simon C. +2 more
We present the results of an abundance analysis of three G and two K dwarfs in the Praesepe open cluster based on high-resolution, moderate signal-to-noise-ratio spectra obtained with the ARC 3.5 m Telescope at Apache Point Observatory. Using a principal component analysis and the BACCHUS automated spectral analysis code, we determined stellar par…
Slitless Solar Imaging Spectroscopy
Kamalabadi, Farzad; Davila, Joseph M.; Oktem, Figen S.
Spectrometers provide our most detailed diagnostics of the solar coronal plasma, and spectral data is routinely used to measure the temperature, density, and flow velocity in coronal features. However, spectrographs suffer from a limited instantaneous field of view (IFOV). Conversely, imaging instruments can provide a relatively large IFOV, but ex…
XMM-Newton and INTEGRALanalysis of the Supergiant Fast X-ray Transient IGR J17354-3255
Hill, A. B.; Bird, A. J.; Sguera, V. +2 more
We present the results of combined INTEGRALand XMM-Newton observations of the supergiant fast X-ray transient (SFXT) IGR J17354-3255. Three XMM-Newton observations of lengths 33.4, 32.5, and 21.9 ks were undertaken, the first an initial pointing to identify the correct source in the field of view and the latter two performed around periastron. Sim…
CCD Observations and Period Change of the Type ab RR Lyrae Star DV Mon
Dambis, A. K.; Berdnikov, L. N.; Kniazev, A. Yu. +3 more
We took a total of 635 B-, V-, and Ic-band CCD frames for the RRab Lyr type variable DVMon, which has a close bright visual companion with a separation of about 1.9'. Observations were made with the 76-cm telescope of the South African Astronomical Observatory (SAAO, South Africa) using SBIG CCD ST-10XME. For the first time, we obtained…
Retrieval of Martian ozone and dust from SPICAM spectrometer for MY27-MY28
Montmessin, Franck; Modak, Ashimananda; Sheel, Varun
Ozone (O3) is important in the stabilisation of CO_{{2}} in the Martian atmosphere and thus it is important to study the spatio-temporal variability of O_{{3}}. We retrieve two years of total columnar O_{{3}} from raw spectral data provided by the SPectroscopy for the Investigation of the Characteristics of the Atmosphere of Mars (SPICA…
Deep lensing with a twist: E and B modes in a field with multiple lenses
Tyson, J. Anthony; Jee, M. James; Bradshaw, Andrew K.
We explore the weak lensing E- and B-mode shear signals of a field of galaxy clusters using both large-scale structure N-body simulations and multicolour Suprime-cam & Hubble Space Telescope observations. Using the ray-traced and observed shears along with photometric redshift catalogues, we generate mass maps of the foreground overdensities b…
A pre-merger stage galaxy cluster: Abell 3733
Caglar, Turgay; Kaya, H. Ilker; Sert, Hakan
The galaxy cluster Abell 3733 (A3733) is a very suitable candidate in addressing dynamical processes throughout galaxy cluster mergers. This study shows structural analysis results of A3733 (z = 0.038) based on X-ray and optical data. According to X-ray luminosity map, A3733 hosts two sub-structures separated in the sky by 0.25 Mpc, and the two di…