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Presents narrow-band imaging observations of the Seyfert 2 galaxy NGC5252. Research methods.

As part of our project for studying bright (V < 10 mag) eclipsing binaries discovered using images from the NASA STEREO mission we are accumulating follow-up observations with the goal of complete characterization of the systems. The full complement of data consist of light curves extracted from STEREO photometry, wide coverage Echelle spectra obtained at Apache Point Observatory for stellar characterization and Coude spectra obtained at NAO Rozhen for radial velocity curves. Here we present physical parameters-masses and radii-for six short period (P < 3d) single line binary systems containing low-mass components. [ABSTRACT FROM AUTHOR]

We present DOHA, a new algorithm for cotrending photometric light curves obtained by transiting exoplanet surveys. The algorithm employs a novel approach to the traditional 'differential photometry' technique, by selecting the most suitable comparison star for each target light curve, using a two-step correlation search. Extensive tests on real data reveal that DOHA corrects both intra-night variations and long-term systematics affecting the data. Statistical studies conducted on a sample of ~9500 light curves from the Qatar Exoplanet Survey reveal that DOHA-corrected light curves show an rms improvement of a factor of ~2, compared to the raw light curves. In addition, we show that the transit detection probability in our sample can increase considerably, even up to a factor of 7, after applying DOHA. [ABSTRACT FROM AUTHOR]

We report the discovery of a transiting, gas giant circumbinary planet orbiting the eclipsing binary KIC 4862625 and describe our independent discovery of the two transiting planets orbiting Kepler-47. We describe a simple and semi-automated procedure for identifying individual transits in light curves and present our follow-up measurements of the two circumbinary systems. For the KIC 4862625 system, the 0.52 ± 0.018 RJupiter radius planet revolves every ~138 days and occults the 1.47±0.08M⊙, 1.7±0.06 R⊙ F8 IV primary star producing aperiodic transits of variable durations commensurate with the configuration of the eclipsing binary star. Our best-fit model indicates the orbit has a semi-major axis of 0.64 AU and is slightly eccentric, e = 0.1. For the Kepler-47 system, we confirm the results of Orosz et al. Modulations in the radial velocity of KIC 4862625A are measured both spectroscopically and photometrically, i.e., via Doppler boosting, and produce similar results. [ABSTRACT FROM AUTHOR]

We present Space Telescope Imaging Spectrograph emission-line spectra of the central regions of the spiral galaxies NGC 1300 and 2748. From the derived kinematics of the nuclear gas we have found evidence for central supermassive black holes in both galaxies. The estimated masses of the black holes in NGC 1300 and 2748 areand, respectively (both at the 95 per cent confidence level). These two black hole mass estimates contribute to the poorly sampled low-mass end of the nuclear black hole mass spectrum. [ABSTRACT FROM AUTHOR]

ABSTRACT We report, as a part of a long-term study of infrared (IR) mergers and IR quasi-stellar objects (QSOs), detailed spectroscopic evidence for outflow (OF) and Wolf–Rayet (WR) features in the nearby mergers NGC 4038/39 and IRAS 23128-5919 (with low-velocity OF); and the nearby QSOs IRAS 01003-2238 and 13218+0552 (with extreme velocity OF, EVOF). We also study the presence of EVOF in a complete sample of ultraluminous IR galaxies and QSOs (‘The IRAS 1-Jy Survey’, 118 objects). We found EVOF in IRAS 11119+3257, 14394+5332, 15130-1958 and 15462-0450. The low-velocity OF components were detected mainly in objects with starburst processes, i.e. OF associated with galactic winds generated in multiple type II supernova (SN) explosions and massive stars. Meanwhile the EVOF were detected mainly in objects with strong starburst plus obscured IR QSOs; which suggests that the coexistence of both processes could generate EVOF. Hubble Space Telescope (HST) images of IR+BAL+Fe iiQSOs show in practically all of these objects ‘arc or shell’ features probably associated with galactic winds [i.e. with multiple type II SN explosions or with starburst+active galactic nuclei (AGN)] or merger processes. In addition, we analyse the presence of Wolf–Rayet features in part of the large sample of bright PG-QSOs. We found possible WR features in the Fe iiPG-QSOs PG 1244+026, 1444+407, 1448+273 and 1535+547. The results are discussed mainly within the framework of the composite scenario: starburst+AGN. We analyse the presence of extreme starburst and galactic winds as a possible link between IR mergers and IR QSOs. Finally, we discuss the probable role of mergers, extreme starburst and galactic winds processes in BAL-QSOs and galaxies in formation. [ABSTRACT FROM AUTHOR]

A correction to the article "Kepler-413B: A Slightly Misaligned, Neptune-Size Transiting Circumbinary Planet" by V. B. Kostov that was published in the journal in 2014 is presented.

We report the discovery of a transiting, Rp = 4.347 ± 0.099R⊕, circumbinary planet (CBP) orbiting the KeplerK+M eclipsing binary (EB) system KIC 12351927 (Kepler-413) every ∼66 days on an eccentric orbit with ap = 0.355 ± 0.002 AU, ep = 0.118 ± 0.002. The two stars, with MA = 0.820 ± 0.015 M☼, RA = 0.776 ± 0.009 R☼ and MB = 0.542 ± 0.008 M☼, RB = 0.484 ± 0.024 R☼, respectively, revolve around each other every 10.11615 ± 0.00001 days on a nearly circular (eEB = 0.037 ± 0.002) orbit. The orbital plane of the EB is slightly inclined to the line of sight (iEB = 87.°33 ± 0.°06), while that of the planet is inclined by ∼2.°5 to the binary plane at the reference epoch. Orbital precession with a period of ∼11 yr causes the inclination of the latter to the sky plane to continuously change. As a result, the planet often fails to transit the primary star at inferior conjunction, causing stretches of hundreds of days with no transits (corresponding to multiple planetary orbital periods). We predict that the next transit will not occur until 2020. The orbital configuration of the system places the planet slightly closer to its host stars than the inner edge of the extended habitable zone. Additionally, the orbital configuration of the system is such that the CBP may experience Cassini State dynamics under the influence of the EB, in which the planet's obliquity precesses with a rate comparable to its orbital precession. Depending on the angular precession frequency of the CBP, it could potentially undergo obliquity fluctuations of dozens of degrees (and complex seasonal cycles) on precession timescales. [ABSTRACT FROM AUTHOR]