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R. Gil-Merino L. J. Goicoechea M. Serra-Ricart A. Oscoz D. Alcalde E. Mediavilla 《Monthly notices of the Royal Astronomical Society》2001,322(2):397-410
From optical R -band data of the double quasar QSO 0957+561A,B, we made two new difference light curves (with an overlap of about 330 d between the time-shifted light curve for the A image and the magnitude-shifted light curve for the B image). We observed noisy behaviours around the zero line and no short time-scale events (with a duration of months), where the term 'event' refers to a prominent feature that may be a result of microlensing or another source of variability. Only one event lasting two weeks and rising −33 mmag was found . Measured constraints on the possible microlensing variability can be used to obtain information on the granularity of the dark matter in the main lensing galaxy and the size of the source. In addition, one can also test the ability of the observational noise to cause the rms averages and the local features of the difference signals. We focused on this last issue. The combined photometries were related to a process consisting of an intrinsic signal plus a Gaussian observational noise. The intrinsic signal has been assumed to be either a smooth function (polynomial), a smooth function plus a stationary noise process, or a correlated stationary process . Using these three pictures without microlensing, we derived some models totally consistent with the observations. We finally discussed the sensitivity of our telescope (at Teide Observatory) to several classes of microlensing variability. 相似文献
2.
Licandro J. Bellot Rubio L. R. Casas R. Gómez A. Kidger M. R. Sabalisk N. Santos-Sanz P. Serra-Ricart M. Torres-Chico R. Oscoz A. Jorda L. Denicolo G. 《Earth, Moon, and Planets》1997,77(3):199-206
Monitoring of the near-nucleus activity of C/1995 O1 (Hale-Bopp) began in Teide Observatory in August 1995. During 1996 the
comet was observed on 72 nights between March 26 and November 13. A permanent fan structure was observed towards the north
during the whole period of observation. The position angle of the axis of this fan was measured and its variations with time
were used to determine the position of the North Pole of the cometary nucleus.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
3.
Vaduvescu O. Aznar Macias A. Wilson T. G. Zegmott T. Pérez Toledo F. M. Predatu M. Gherase R. Pinter V. Pozo Nunez F. Ulaczyk K. Soszyński I. Mróz P. Wrona M. Iwanek P. Szymanski M. Udalski A. Char F. Salas Olave H. Aravena-Rojas G. Vergara A. C. Saez C. Unda-Sanzana E. Alcalde B. de Burgos A. Nespral D. Galera-Rosillo R. Amos N. J. Hibbert J. López-Comazzi A. Oey J. Serra-Ricart M. Licandro J. Popescu M. 《Earth, Moon, and Planets》2022,126(2):1-26
Earth, Moon, and Planets - The Perseverance rover (Mars 2020) mission, the first step in NASA’s Mars Sample Return (MSR) program, will select samples for caching based on their potential to... 相似文献
4.
A. Ullán L. J. Goicoechea J. A. Muñoz E. Mediavilla M. Serra-Ricart E. Puga D. Alcalde A. Oscoz R. Barrena 《Monthly notices of the Royal Astronomical Society》2003,346(2):415-423
The Gravitational Lenses International Time Project (GLITP) collaboration observed the first gravitational lens system (QSO 0957+561) from 2000 February 3 to March 31. The daily VR observations were made with the 2.56-m Nordic Optical Telescope at Roque de los Muchachos Observatory, La Palma, Spain. We have derived detailed and robust VR light curves of the two components Q0957+561A and Q0957+561B. In spite of the excellent sampling rate, we have not found evidence in favour of true daily variability. With respect to variability on time-scales of several weeks, we measure VR gradients of about −0.8 mmag d−1 in Q0957+561A and +0.3 mmag d−1 in Q0957+561B. The gradients are very probably originated in the far source. Thus, adopting this reasonable hypothesis (intrinsic variability), we compare them to the expected gradients during the evolution of a compact supernova remnant at the redshift of the source quasar. The starburst scenario is roughly consistent with some former events, but the new gradients do not seem to be caused by supernova remnant activity. 相似文献
5.
O. Vaduvescu A. Aznar Macias V. Tudor M. Predatu A. Galád Š. Gajdoš J. Világi H. F. Stevance R. Errmann E. Unda-Sanzana F. Char N. Peixinho M. Popescu A. Sonka R. Cornea O. Suciu R. Toma P. Santos-Sanz A. Sota J. Licandro M. Serra-Ricart D. Morate T. Mocnik M. Diaz Alfaro F. Lopez-Martinez J. McCormac N. Humphries 《Earth, Moon, and Planets》2017,120(2):41-100
This data paper presents lightcurves of 101 near Earth asteroids (NEAs) observed mostly between 2014 and 2017 as part of the EURONEAR photometric survey using 11 telescopes with diameters between 0.4 and 4.2 m located in Spain, Chile, Slovakia and Romania. Most targets had no published data at the time of observing, but some objects were observed in the same period mainly by B. Warner, allowing us to confirm or improve the existing results. To plan the runs and select the targets, we developed the public Long Planning tool in PHP. For preliminary data reduction and rapid follow-up planning we developed the LiDAS pipeline in Python and IRAF. For final data reduction, flux calibration, night linkage and Fourier fitting, we used mainly MPO Canopus. Periods of 18 targets are presented for the first time, and we could solve or constrain rotation for 16 of them. We secured periods for 45 targets (\(U\sim 3\)), found candidate periods for other 16 targets (\(U\sim 2\)), and we propose tentative periods for other 32 targets (\(U\sim 1\)). We observed 7 known or candidate binary NEAs, fiting 3 of them (2102 Tantalus, 5143 Heracles and 68348). We observed 8 known or candidate tumbling NEAs, deriving primary periods for 3 objects (9400, 242708 and 470510). We evidenced rapid oscillations (few minutes) and could fit fast tentative periods TP2 for 5 large newly suggested tumbling or binary candidates (27346, 112985, 285625, 377732, 408980), probably discovering at least one new binary NEA (2011 WO41). We resolved periods of 4 special objects which include two proposed space mission targets (163249 and 101955 Bennu), one very fast rotator NEA discovered by EURONEAR (2014 NL52) and the “Halloween asteroid” (2015 TB145). Using Mercator in simultaneous 3 band MAIA imaging, we could evidence for the first time clear variation in the color lightcurves of 10 NEAs. The periods derived from the g–r color lightcurves are found to match individual band period fits for 4 NEAs (27346, 86067, 112985 and 275976). 相似文献
6.
Lipunov V. M. Kuznetsov A. S. Gorbovskoy E. S. Kornilov V. G. Tyurina N. V. Vladimirov V. V. Krushinskiy V. V. Zalozhnykh I. S. Vlasenko D. M. Zimnukhov D. S. Balanutsa P. V. Gabovich A. Shakura N. I. Giovanelli F. Titarchuk L. G. Buckley D. A. H. Gress O. Budnev N. Rebolo R. Serra-Ricart M. Tlatov A. G. Senik V. A. Yurkov V. V. Ershova O. Grinshpun V. G. Ishmukhametova Yu. V. 《Astronomy Reports》2019,63(7):534-549
2070 unique, homogeneous photometric and polarization observations of the microquasar in a binary system with a black hole V404 Cyg/GS2023+338 obtained in 2015 with the MASTER global network of robotic telescopes (16 robotic telescopes located at eight points on the Earth in Russia, Spain, South Africa, and Argentina) are presented. MASTER was the first telescope network to obtain optical observations of the microquasar after its gamma-ray outburst in 2015. Observations were carried out from 18:34:09 UT on June 15, 2015 until December 2015 in four polarizations and in the four standard BV RI filters. The paper presents the results of these observations and a comparative analysis of optical and X-ray data. The observations confirm the previously discovered super-long delays of the optical radiation relative to the X-ray outbursts. Possible mechanisms causing the delay in the optical variations relative to the X-ray variations are discussed. Variability of the optical polarization discovered earlier is confirmed another similar episode reported.
相似文献7.
A. Fassia W. P. S. Meikle W. D. Vacca S. N. Kemp N. A. Walton D. L. Pollacco S. Smartt A. Oscoz A. Aragón-Salamanca S. Bennett T. G. Hawarden A. Alonso D. Alcalde A. Pedrosa J. Telting M. J. Arevalo H. J. Deeg F. Garzón A. Gómez-Roldán G. Gómez C. Gutiérrez S. López M. Rozas M. Serra-Ricart M. R. Zapatero-Osorio 《Monthly notices of the Royal Astronomical Society》2000,318(4):1093-1104
We present contemporaneous optical and infrared (IR) photometric observations of the Type IIn SN 1998S covering the period between 11 and 146 d after discovery. The IR data constitute the first ever IR light curves of a Type IIn supernova. We use blackbody and spline fits to the photometry to examine the luminosity evolution. During the first 2–3 months, the luminosity is dominated by the release of shock-deposited energy in the ejecta. After ∼100 d the luminosity is powered mostly by the deposition of radioactive decay energy from 0.15±0.05 M⊙ of 56 Ni which was produced in the explosion. We also report the discovery of an astonishingly high IR excess, K − L '=2.5, that was present at day 130. We interpret this as being due to thermal emission from dust grains in the vicinity of the supernova. We argue that to produce such a high IR luminosity so soon after the explosion, the dust must be pre-existing and so is located in the circumstellar medium of the progenitor. The dust could be heated either by the UV/optical flash (IR echo) or by the X-rays from the interaction of the ejecta with the circumstellar material. 相似文献
8.
R. I. Hynes P. A. Charles C. A. Haswell J. Casares C. Zurita M. Serra-Ricart 《Monthly notices of the Royal Astronomical Society》2001,324(1):180-190
We present time-resolved spectroscopy of the soft X-ray transient XTE J2123–058 in outburst. A useful spectral coverage of 3700–6700 Å was achieved spanning two orbits of the binary, with single-epoch coverage extending to ∼9000 Å. The optical spectrum approximates a steep blue power law, consistent with emission on the Rayleigh–Jeans tail of a hot blackbody spectrum. The strongest spectral lines are He ii 4686 Å and C iii /N iii 4640 Å (Bowen blend) in emission. Their relative strengths suggest that XTE J2123–058 was formed in the Galactic plane, not in the halo. Other weak emission lines of He ii and C iv are present, and Balmer lines show a complex structure, blended with He ii . He ii 4686-Å profiles show a complex multiple S-wave structure, with the strongest component appearing at low velocities in the lower-left quadrant of a Doppler tomogram. H α shows transient absorption between phases 0.35 and 0.55. Both of these effects appear to be analogous to similar behaviour in SW Sex type cataclysmic variables. We therefore consider whether the spectral line behaviour of XTE J2123–058 can be explained by the same models invoked for those systems. 相似文献
9.
Zimnukhov D. S. Lipunov V. M. Gorbovskoy E. S. Kornilov V. G. Tyurina N. V. Chazov V. V. Gabovich A. V. Balanutsa P. V. Vladimirov V. V. Gress O. A. Kuznetsov A. S. Rebolo Lopez R. Serra-Ricart M. Yurkov V. V. Vlasenko D. M. Budnev N. M. Sergienko Yu. P. 《Astronomy Reports》2019,63(12):1056-1068
The results of white-light photometry for a uniquely long series of data (13.5 hours of observations, 1124 measurements) for the Near-Earth Asteroid (NEA) 2015 TB145 are presented. These data were obtained with the MASTER-Amur and MASTER-Tavrida wide-field robotic telescopes of the Mobile Astronomical System of Telescope-Robots (MASTER) global network of Lomonosov Moscow State University, located in the Crimea and in Blagoveshchensk. The object moved by more than 120° during the observations. The asteroid passed the point of closest approach to the Earth, i.e., observations were carried during both the asteroid's approach and recession. Thus, due to the geometry of the passage, this series of observations contains information about the asteroid viewed at different angles, and is very suitable for precisely determining the shape of the object. Mathematical modeling of the light curve and astrometric positions (with the Asteroids3D code) was carried out, and the probable shape of the asteroid (conical) and the rotation period of 5.9 hours were obtained, as well as the orientation of the rotation axis in ecliptic coordinates: longitude λ = 53°, latitude β = −20°. The derived period coincides with twice the period of 2.9 hours obtained by other observers published earlier, within the uncertainties.
相似文献10.
O. A. Ershova V. M. Lipunov E. S. Gorbovskoy N. V. Tyurina V. G. Kornilov D. S. Zimnukhov A. Gabovich O. A. Gress N. M. Budnev V. V. Yurkov V. V. Vladimirov A. S. Kuznetsov P. V. Balanutsa R. Rebolo M. Serra-Ricart D. Buckley R. Podesta H. Levato C. Lopez F. Podesta C. Francile C. Mallamaci S. A. Yazev D. M. Vlasenko A. Tlatov V. Senik V. Grinshpun A. Chasovnikov V. Topolev A. Pozdnyakov K. Zhirkov D. Kuvshinov F. Balakin 《Astronomy Reports》2020,64(2):126-158
We present the results of early observations for 130 error-boxes of gamma-ray bursts performed with the Mobile Astronomical System of TElescope-Robots (MASTER) global network of robotic telescopes from Moscow State University in fully automatic mode (2011–2017). Among them, GRB 130907A, GRB 120811C, GRB 110801A, GRB 120404A, GRB 140129B, GRB140311B, and GRB 160227A are considered in details. Among these 130 gamma-ray bursts, in the first 60 s after the trigger with the Swift, Fermi, INTEGRAL, MAXI, Lomonosov, and Konus-Wind orbital observatories, the MASTER was pointed on 51 gamma-ray bursts, being the leader in terms of the first pointing. Full observation automation and MASTER own real-time image processing software allowed us to obtain unique data on early optical emission that accompanied 44 gamma-ray bursts (GRB 110801A, GRB120106A, GRB 120404A, GRB 120811C, GRB 120907A, GRB 121011A, GRB 130122A, GRB 130907A, GRB 131030A, GRB 131125A, GRB 140103A, GRB 140108A, GRB 140129B, GRB 140206A, GRB 140304A, GRB 140311B, GRB 140512A, GRB 140629A, GRB 140801A, GRB140907A, GRB 140930B, GRB141028A, GRB 141225A, GRB 150210A, GRB 150211A, GRB 150301B, GRB 150323C, GRB 150404A/Fermi trigger 449861706, GRB 150403A, GRB 150413A, GRB 150518A, GRB 150627A, GRB 151021A, GRB 151215A, GRB 160104A, GRB 160117B, GRB 160131A, GRB 160227A, GRB 160425A, GRB 160611A, GRB 160625B, GRB 160804A, GRB 160910A, GRB 161017A, GRB 161117A, GRB 161119A). We obtain light curves for 13 gamma-ray bursts among the above listed ones and compare the data in the optical (MASTER), X-ray (Swift-XRT), and hard X-ray (Swift-BAT) ranges. 相似文献
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