Astronomical Journal最新文献_第3页

SNaX: A Database of Supernova X-Ray Light Curves. SNaX：超新星 X 射线光曲线数据库。

IF 5.3 2区物理与天体物理

Astronomical Journal Pub Date : 2017-06-01 Epub Date: 2017-05-09 DOI: 10.3847/1538-3881/aa6d50

Mathias Ross, Vikram V Dwarkadas

{"title":"SNaX: A Database of Supernova X-Ray Light Curves.","authors":"Mathias Ross, Vikram V Dwarkadas","doi":"10.3847/1538-3881/aa6d50","DOIUrl":"10.3847/1538-3881/aa6d50","url":null,"abstract":"We present the Supernova X-ray Database (SNaX), a compilation of the X-ray data from young supernovae (SNe). The database includes the X-ray fluxes and luminosities of young SNe, from days to years after outburst. The original goal and intent of this study was to present a database of Type IIn SNe (SNe IIn), which we have accomplished. Our ongoing goal is to expand the database to include all SNe for which published data are available. The database interface allows one to search for SNe using various criteria, plot all or selected data points, and download both the data and the plot. The plotting facility allows for significant customization. There is also a facility for the user to submit data that can be directly incorporated into the database. We include an option to fit the decay of any given SN light curve with a power-law. The database includes a conversion of most data points to a common 0.3-8 keV band so that SN light curves may be directly compared with each other. A mailing list has been set up to disseminate information about the database. We outline the structure and function of the database, describe its various features, and outline the plans for future expansion.","PeriodicalId":55582,"journal":{"name":"Astronomical Journal","volume":"153 6","pages":""},"PeriodicalIF":5.3,"publicationDate":"2017-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7735204/pdf/nihms-1649604.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38727317","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

FUSE Spectroscopy of the Accreting Hot Components in Symbiotic Variables. 共生变量中吸积热分量的熔断光谱。

IF 5.3 2区物理与天体物理

Astronomical Journal Pub Date : 2017-04-01 Epub Date: 2017-03-17 DOI: 10.3847/1538-3881/aa62a9

Edward M Sion, Patrick Godon, Joanna Mikolajewska, Bassem Sabra, Craig Kolobow

{"title":"FUSE Spectroscopy of the Accreting Hot Components in Symbiotic Variables.","authors":"Edward M Sion, Patrick Godon, Joanna Mikolajewska, Bassem Sabra, Craig Kolobow","doi":"10.3847/1538-3881/aa62a9","DOIUrl":"https://doi.org/10.3847/1538-3881/aa62a9","url":null,"abstract":"We have conducted a spectroscopic analysis of the far ultraviolet archival spectra of four symbiotic variables, EG And, AE Ara, CQ Dra and RW Hya. RW Hya and EG And have never had a recorded outburst while CQ Dra and AE Ara have outburst histories. We analyze these systems while they are in quiescence in order to help reveal the physical properties of their hot components via comparisons of the observations with optically thick accretion disk models and NLTE model white dwarf photospheres. We have extended the wavelength coverage down to the Lyman Limit with FUSE spectra. We find that the hot component in RW Hya is a low mass white dwarf with a surface temperature of 160,000K. We re-examine whether or not the symbiotic system CQ Dra is a triple system with a red giant transferring matter to a hot component made up of a cataclysmic variable in which the white dwarf has a surface temperature as low as ∼20,000K. The very small size of the hot component contributing to the shortest wavelengths of the FUSE spectrum of CQ Dra agrees with an optically thick and geometrically thin (∼4% of the WD surface) hot (∼ 120, 000K) boundary layer. Our analysis of EG And reveals that its hot component is a hot, bare, low mass white dwarf with a surface temperature of 80-95,000K, with a surface gravity log(g) = 7.5. For AE Ara, we also find that a low gravity (log(g) ∼ 6) hot (T ∼ 130, 000K) WD accounts for the hot component.","PeriodicalId":55582,"journal":{"name":"Astronomical Journal","volume":"153 No 4","pages":""},"PeriodicalIF":5.3,"publicationDate":"2017-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3847/1538-3881/aa62a9","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"35842321","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

A SEARCH FOR LOST PLANETS IN THE KEPLER MULTI-PLANET SYSTEMS AND THE DISCOVERY OF A LONG PERIOD, NEPTUNE-SIZED EXOPLANET KEPLER-150 F. 在开普勒多行星系统中寻找丢失的行星，并发现了一颗长时间的、海王星大小的系外行星开普勒- 150f。

IF 5.3 2区物理与天体物理

Astronomical Journal Pub Date : 2017-04-01 Epub Date: 2017-03-28 DOI: 10.3847/1538-3881/aa62ad

Joseph R Schmitt, Jon M Jenkins, Debra A Fischer

{"title":"A SEARCH FOR LOST PLANETS IN THE KEPLER MULTI-PLANET SYSTEMS AND THE DISCOVERY OF A LONG PERIOD, NEPTUNE-SIZED EXOPLANET KEPLER-150 F.","authors":"Joseph R Schmitt, Jon M Jenkins, Debra A Fischer","doi":"10.3847/1538-3881/aa62ad","DOIUrl":"https://doi.org/10.3847/1538-3881/aa62ad","url":null,"abstract":"The vast majority of the 4700 confirmed planets and planet candidates discovered by the Kepler space telescope were first found by the Kepler pipeline. In the pipeline, after a transit signal is found, all data points associated with those transits are removed, creating a \"Swiss cheese\"-like light curve full of holes, which is then used for subsequent transit searches. These holes could render an additional planet undetectable (or \"lost\"). We examine a sample of 114 stars with 3+ confirmed planets to see the effect that this \"Swiss cheesing\" may have. A simulation determined that the probability that a transiting planet is lost due to the transit masking is low, but non-neglible, reaching a plateau at ~3.3% lost in the period range of P = 400 - 500 days. We then model the transits in all quarters of each star and subtract out the transit signals, restoring the in-transit data points, and use the Kepler pipeline to search the transit-subtracted (i.e., transit-cleaned) light curves. However, the pipeline did not discover any credible new transit signals. This demonstrates the validity and robustness of the Kepler pipeline's choice to use transit masking over transit subtraction. However, a follow-up visual search through all the transit-subtracted data, which allows for easier visual identification of new transits, revealed the existence of a new, Neptune-sized exoplanet. Kepler-150 f (P = 637.2 days, RP = 3.86 R⊕) is confirmed using a combination of false positive probability analysis, transit duration analysis, and the planet multiplicity argument.","PeriodicalId":55582,"journal":{"name":"Astronomical Journal","volume":"153 No 4","pages":""},"PeriodicalIF":5.3,"publicationDate":"2017-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3847/1538-3881/aa62ad","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"35772083","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 13

Far Ultraviolet Spectroscopy of Old Novae. II. RR Pic, V533 Her, and DI Lac. 老新星的远紫外光谱。2RR Pic, V533 Her和DI Lac。

IF 5.3 2区物理与天体物理

Astronomical Journal Pub Date : 2017-03-01 Epub Date: 2017-02-15 DOI: 10.3847/1538-3881/153/3/109

Edward M Sion, Patrick Godon, Liam Jones

{"title":"Far Ultraviolet Spectroscopy of Old Novae. II. RR Pic, V533 Her, and DI Lac.","authors":"Edward M Sion, Patrick Godon, Liam Jones","doi":"10.3847/1538-3881/153/3/109","DOIUrl":"https://doi.org/10.3847/1538-3881/153/3/109","url":null,"abstract":"The old novae V533 Her (Nova Her 1963), DI Lac (Nova Lac 1910), and RR Pic (Nova Pic 1891) are in (or near) their quiescent stage, following their nova explosions, and continue to accrete at a high rate in the aftermath of their explosions. They exhibit continua that are steeply rising into the FUV, as well as absorption lines and emission lines of uncertain origin. All three have Far Ultraviolet Spectroscopic Explorer (FUSE) spectra that offer not only higher spectral resolution but also wavelength coverage extending down to the Lyman Limit. For DI Lac, we have matched these FUSE spectra with existing archival International Ultraviolet Explorer spectral coverage to broaden the FUV wavelength coverage. We adopted the newly determined interstellar reddening corrections of Selvelli & Gilmozzi. The dereddened FUV spectra have been modeled with our grids of optically thick accretion disks and hot, NLTE white dwarf (WD) photospheres. The results of our modeling analysis indicate that the hot components in RR Pic and V533 Her are likely to be accretion disks with mass accretion rates of 10-8M⊙ yr-1 and 10-9M⊙ yr-1 respectively. However, the disk cannot produce the observed absorption lines. For the WD to be the source of the absorption lines in these two systems, it must be very hot, with a radius several times its expected size (because the WD in these systems is massive, it has a smaller radius). For DI Lac, we find the best fit to be a disk with Ṁ = 10-10M⊙ yr-1 with a 30,000 K WD.","PeriodicalId":55582,"journal":{"name":"Astronomical Journal","volume":"153 No 3","pages":""},"PeriodicalIF":5.3,"publicationDate":"2017-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3847/1538-3881/153/3/109","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"35842319","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Second Epoch VLBA Calibrator Survey Observations - VCS-II. 第二纪元VLBA校准测量观测- VCS-II。

IF 5.3 2区物理与天体物理

Astronomical Journal Pub Date : 2016-05-27 DOI: 10.3847/0004-6256/151/6/154

David Gordon, Christopher Jacobs, Anthony Beasley, Alison Peck, Ralph Gaume, Patrick Charlot, Alan Fey, Chopo Ma, Oleg Titov, David Boboltz

{"title":"Second Epoch VLBA Calibrator Survey Observations - VCS-II.","authors":"David Gordon, Christopher Jacobs, Anthony Beasley, Alison Peck, Ralph Gaume, Patrick Charlot, Alan Fey, Chopo Ma, Oleg Titov, David Boboltz","doi":"10.3847/0004-6256/151/6/154","DOIUrl":"https://doi.org/10.3847/0004-6256/151/6/154","url":null,"abstract":"Six very successful VLBA calibrator survey campaigns were run between 1994 and 2007 to build up a large list of compact radio sources with positions precise enough for use as VLBI phase reference calibrators. We report on the results of a second epoch VLBA Calibrator Survey campaign (VCS-II) in which 2400 VCS sources were re-observed at X and S bands in order to improve the upcoming third realization of the International Celestial Reference Frame (ICRF3) as well as to improve their usefulness as VLBI phase reference calibrators. In this survey, some 2062 previously detected sources and 324 previously undetected sources were detected and revised positions are presented. Average position uncertainties for the re-observed sources were reduced from 1.14 and 1.98 mas to 0.24 and 0.41 mas in RA and Declination, respectively, or by nearly a factor of 5. Minimum detected flux values were approximately 15 and 28 mJy in X and S bands, respectively, and median total fluxes are approximately 230 and 280 mJy. The vast majority of these sources are flat-spectrum sources, with ~82% having spectral indices greater than -0.5.","PeriodicalId":55582,"journal":{"name":"Astronomical Journal","volume":"151 6","pages":""},"PeriodicalIF":5.3,"publicationDate":"2016-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3847/0004-6256/151/6/154","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"36253174","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 42

Far Ultraviolet Spectroscopy of Old Novae I. V603 Aquila. 天鹰座老新星I. V603的远紫外光谱分析。

IF 5.3 2区物理与天体物理

Astronomical Journal Pub Date : 2015-07-01 Epub Date: 2015-07-07 DOI: 10.1088/0004-6256/150/1/36

Edward M Sion, Patrick Godon, Alexandra Bisol

引用次数: 1

2MASS J035523.37+113343.7: A YOUNG, DUSTY, NEARBY, ISOLATED BROWN DWARF RESEMBLING A GIANT EXOPLANET. 2质量J035523.37+113343.7：一颗年轻、多尘、附近孤立的棕色矮星，类似于一颗巨大的系外行星。

IF 5.3 2区物理与天体物理

Astronomical Journal Pub Date : 2013-01-01 Epub Date: 2012-11-20 DOI: 10.1088/0004-6256/145/1/2

Jacqueline K Faherty, Emily L Rice, Kelle L Cruz, Eric E Mamajek, Alejandro Núñez

{"title":"2MASS J035523.37+113343.7: A YOUNG, DUSTY, NEARBY, ISOLATED BROWN DWARF RESEMBLING A GIANT EXOPLANET.","authors":"Jacqueline K Faherty, Emily L Rice, Kelle L Cruz, Eric E Mamajek, Alejandro Núñez","doi":"10.1088/0004-6256/145/1/2","DOIUrl":"10.1088/0004-6256/145/1/2","url":null,"abstract":"We present parallax and proper motion measurements, near-infrared spectra, and WISE photometry for the low surface gravity L5γ dwarf 2MASSJ035523.37+113343.7 (2M0355). We use these data to evaluate photometric, spectral, and kinematic signatures of youth as 2M0355 is the reddest isolated L dwarf yet classified. We confirm its low-gravity spectral morphology and find a strong resemblance to the sharp triangular shaped H-band spectrum of the ∼10 Myr planetary-mass object 2M1207b. We find that 2M0355 is underluminous compared to a normal field L5 dwarf in the optical and MKO J, H, and K bands and transitions to being overluminous from 3-12 μm, indicating that enhanced photospheric dust shifts flux to longer wavelengths for young, low-gravity objects, creating a red spectral energy distribution. Investigating the near-infrared color magnitude diagram for brown dwarfs confirms that 2M0355 is redder and underluminous compared to the known brown dwarf population, similar to the peculiarities of directly imaged exoplanets 2M1207b and HR8799bcd. We calculate UVW space velocities and find that the motion of 2M0355 is consistent with young disk objects (< 2-3 Gyr) and it shows a high likelihood of membership in the AB Doradus association.","PeriodicalId":55582,"journal":{"name":"Astronomical Journal","volume":"2 ","pages":""},"PeriodicalIF":5.3,"publicationDate":"2013-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1088/0004-6256/145/1/2","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"36786799","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 125

DISCOVERY OF TWO VERY WIDE BINARIES WITH ULTRACOOL COMPANIONS AND A NEW BROWN DWARF AT THE L/T TRANSITION. 在l / t跃迁中发现了两个非常宽的双星和一个新的褐矮星。

IF 5.3 2区物理与天体物理

Astronomical Journal Pub Date : 2012-01-01 DOI: 10.1088/0004-6256/144/6/180

Koraljka Mužić, Jacqueline Radigan, Ray Jayawardhana, Valentin D Ivanov, Jacqueline K Faherty, Radostin G Kurtev, Alejandro Núñez, Henri M J Boffin, Olivier Hainaut, Kelle Cruz, David Jones, Stanimir Metchev, Amy Tyndall, Jura Borissova

{"title":"DISCOVERY OF TWO VERY WIDE BINARIES WITH ULTRACOOL COMPANIONS AND A NEW BROWN DWARF AT THE L/T TRANSITION.","authors":"Koraljka Mužić, Jacqueline Radigan, Ray Jayawardhana, Valentin D Ivanov, Jacqueline K Faherty, Radostin G Kurtev, Alejandro Núñez, Henri M J Boffin, Olivier Hainaut, Kelle Cruz, David Jones, Stanimir Metchev, Amy Tyndall, Jura Borissova","doi":"10.1088/0004-6256/144/6/180","DOIUrl":"https://doi.org/10.1088/0004-6256/144/6/180","url":null,"abstract":"We present the discovery and spectroscopic follow-up of a nearby late-type L dwarf (2M0614+3950), and two extremely wide very-low-mass binary systems (2M0525-7425AB and 2M1348-1344AB), resulting from our search for common proper motion pairs containing ultracool components in the Two Micron All Sky Survey (2MASS) and the Wide-field Infrared Survey Explorer (WISE) catalogs. The near-infrared spectrum of 2M0614+3950 indicates a spectral type L9 ± 1 object residing at a distance of 26.0 ± 1.8 pc. The optical spectrum of 2M0525-7425A reveals an M3.0 ± 0.5 dwarf primary, accompanied by a secondary previously classified as L2. The system has an angular separation of ~ 44″, equivalent to ~ 2000 AU at distance of 46.0 ± 3.0 pc. Using optical and infrared spectra, respectively, we classify the components of 2M1348-1344AB as M4.5 ± 0.5 and T5.5 ± 1. The angular separation of ~ 68″ is equivalent to ~ 1400 AU at a distance of 20.7 ± 1.4 pc. 2M1348-1344AB is one of only six very wide (separation > 1000 AU) systems containing late T dwarfs known to date.","PeriodicalId":55582,"journal":{"name":"Astronomical Journal","volume":"144 6","pages":""},"PeriodicalIF":5.3,"publicationDate":"2012-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1088/0004-6256/144/6/180","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"36786798","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 18