TY - GEN AU - Szabo, Z. M. AU - Kóspál, Ágnes AU - Ábrahám, Péter AU - Park, Sunkyung AU - Siwak, Michal AU - Green, J. D. AU - Moór, Attila AU - Pál, András AU - Acosta-Pulido, J. A. AU - Lee, J. -E. AU - Cseh, B. AU - Csornyei, G. AU - Hanyecz, O. AU - Könyves-Tóth, Réka AU - Krezinger, M. AU - Kriskovics, Levente AU - Ordasi, A. AU - Sárneczky, Krisztián AU - Seli, B. AU - Szakáts, Róbert AU - Szing, A. AU - Vida, Krisztián TI - VizieR Online Data Catalog: Opt-to-IR monitoring obs. of V1057 Cyg (Szabo+, 2021) PY - 2023 UR - https://m2.mtmt.hu/api/publication/33729197 ID - 33729197 AB - We performed the majority of our photometric observations in B, V, RC, IC , g', r', and i' filters at the Piszkesteto Mountain Station of Konkoly Observatory (Hungary) between 2005 and 2021. Three telescopes with three slightly different optical systems were used: the 1m Ritchey-Chretien-coude (RCC) telescope, the 60/90/180cm Schmidt telescope and the Astro Systeme Austria AZ800 alt-azimuth direct drive 80cm Ritchey-Chretien (RC80) telescope; see Section 2.1. In addition to our national facilities, we occasionally used other telescopes. On 2006 July 20 and 2012 October 13 we obtained B, V, RJ, and IJ images of V1057 Cyg with the IAC80 telescope of the Instituto de Astrofisica de Canarias located at Teide Observatory (Canary Islands, Spain). During 2019 August-September, in parallel with TESS, we additionally observed V1057 Cyg at the Northern Skies Observatory (NSO). We used the 0.4m telescope equipped with BVI filters. We also observed V1057 Cyg with the 2.56m Nordic Optical Telescope (NOT) at the Roque de los Muchachos Observatory, La Palma, in the Canary Islands (Plan ID 61-414, PI: Zs. M. Szabo). For optical imaging we used the Alhambra Faint Object Spectrograph and Camera (ALFOSC) on 2020 August 17. The Bessel BVR filter set was supplemented by an i interference filter, which is similar to the SLOAN i', but with a slightly longer effective wavelength of λeff=0.789um. We obtained NIR images in the J, H, and Ks bands at six epochs between 2006 July 15 and 2012 October 13 using the 1.52m Telescopio Carlos Sanchez (TCS) at the Teide Observatory. We also used the NOTCam instrument on the NOT on 2020 August 29. See Section 2.3. We obtained a new optical spectrum of V1057 Cyg with the high-resolution FIbre-fed Echelle Spectrograph (FIES) instrument on the NOT on 2020 August 17. We used a fiber with a larger entrance aperture of 2.5", which provided a spectral resolution R=25000, covering the 370-900nm wavelength range. V1057 Cyg was also observed with the Bohyunsan Optical Echelle Spectrograph (BOES) installed on the 1.8m telescope at the Bohyunsan Optical Astronomy Observatory (BOAO). It provides R=30000 in the wavelength range ~400-900nm. The first spectrum was obtained on 2012-September-11 and the last on 2018-December-18. See Section 2.4. On 2020 August 29, we used the NOTCam on the NOT to obtain new NIR spectra of V1057 Cyg and Iot Cyg (A5 V) as our telluric standard star in the JHKs bands. We used the low-resolution camera mode (R=2500). See Section 2.5. On 2018 September 6, we observed V1057 Cyg with the Stratospheric Observatory for Infrared Astronomy (SOFIA) using the Faint Object infraRed CAmera for the SOFIA Telescope (FORCAST). We obtained mid-infrared imaging in a series of short exposures in band F111 (10.6-11.6um) totaling ~30s, a single exposure in F056 (5.6um) for 37s and F077 (7.5-8um) for 42s, and R~100-200 spectra with G063 (5-8um) and G227 (17-27um) (Plan ID 06_062, PI: J. D. Green). See Section 2.6. (2 data files). LA - English DB - MTMT ER - TY - JOUR AU - Vinkó, József AU - Thomas, B.P. AU - Wheeler, J.C. AU - Ho, A.Y.Q. AU - Cooper, E.M. AU - Gebhardt, K. AU - Ciardullo, R. AU - Farrow, D.J. AU - Hill, G.J. AU - Jäger, Zoltán AU - Kollatschny, W. AU - Liu, C. AU - Regős, Enikő AU - Sárneczky, Krisztián TI - Searching for Supernovae in HETDEX Data Release 3 JF - ASTROPHYSICAL JOURNAL J2 - ASTROPHYS J VL - 946 PY - 2023 IS - 1 PG - 14 SN - 1538-4357 DO - 10.3847/1538-4357/acbfa8 UR - https://m2.mtmt.hu/api/publication/33728423 ID - 33728423 N1 - Department of Astronomy, University of Texas at Austin, 2515 Speedway, Stop C1400, Austin, 78712-1205, TX, United States Konkoly Observatory, CSFK, Konkoly-Thege M. út 15-17, Budapest, 1121, Hungary ELTE Eötvös Loránd University, Institute of Physics, Pázmány Péter sétány 1/A, Budapest, 1117, Hungary Department of Experimental Physics, University of Szeged, Dóm tér 9, Szeged, 6720, Hungary Department of Astronomy, Cornell University, Ithaca, 14853, NY, United States Department of Astronomy & Astrophysics, The Pennsylvania State University, University Park, 16802, PA, United States Institute for Gravitation and the Cosmos, The Pennsylvania State University, University Park, 16802, PA, United States University Observatory, Fakultät für Physik, Ludwig-Maximilians University Munich, Scheinerstrasse 1, Munich, D-81679, Germany Max-Planck Institut für Extraterrestrische Physik, Giessenbachstrasse 1, Garching, D-85748, Germany McDonald Observatory, The University of Texas at Austin, 2515 Speedway, Stop 1402, Austin, 78712, TX, United States Baja Observatory, University of Szeged, Szegedi út POB 766, Baja, 7900, Hungary ELTE Eötvös Loránd University, Gothard Astrophysical Observatory, Szent Imre h.u. 112, Szombathely, 9700, Hungary MTA-ELTE Exoplanet Research Group, Szent Imre h.u. 112, Szombathely, 9700, Hungary Institut für Astrophysik, Universität Göttingen, Friedrich-Hund Platz 1, Göttingen, D-37077, Germany South-Western Institute for Astronomy Research, Yunnan University, Yunnan, Kunming, 650500, China Export Date: 03 April 2023; Cited By: 0; Correspondence Address: J. Vinkó; Department of Astronomy, University of Texas at Austin, Austin, 2515 Speedway, Stop C1400, 78712-1205, United States; email: vinko@konkoly.hu LA - English DB - MTMT ER - TY - JOUR AU - Kecskemethy, Viktoria AU - Kiss, Csaba AU - Szakáts, Róbert AU - Pál, András AU - Szabó M., Gyula AU - Molnár, László AU - Sárneczky, Krisztián AU - Vinkó, József AU - Szabó, Róbert AU - Marton, Gábor AU - Takácsné Farkas, Anikó AU - Kalup, Csilla AU - Kiss, L. László TI - Light Curves of Trans-Neptunian Objects from the K2 Mission of the Kepler Space Telescope JF - ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES J2 - ASTROPHYS J SUPPL S VL - 264 PY - 2023 IS - 1 PG - 20 SN - 0067-0049 DO - 10.3847/1538-4365/ac9c67 UR - https://m2.mtmt.hu/api/publication/33603304 ID - 33603304 N1 - Funding Agency and Grant Number: National Research, Development and Innovation Office (NKFIH, Hungary) [K-115709, K-138962, PD-116175, KKP-137523, GINOP-2.3.2-15-2016-00003]; Hungarian Academy of Sciences [LP2012-31, LP2018-7/2021]; New National Excellence Programs of the Ministry of Innovation and Technology from the source of the National Research, Development and Innovation Fund [UNKP-19-2, UNKP-20-2, UNKP-21-2]; NASA Science Mission Directorate; NASA [NAS5-26555]; NASA Office of Space Science [NNX09AF08G] Funding text: The research leading to these results has received funding from grants K-115709, K-138962, PD-116175, KKP-137523, and GINOP-2.3.2-15-2016-00003 of the National Research, Development and Innovation Office (NKFIH, Hungary) and grants LP2012-31 and LP2018-7/2021 Lendulet of the Hungarian Academy of Sciences. The research leading to these results has been supported by the UNKP-19-2, UNKP-20-2, and UNKP-21-2 New National Excellence Programs of the Ministry of Innovation and Technology from the source of the National Research, Development and Innovation Fund. Funding for the Kepler and K2 missions is provided by the NASA Science Mission Directorate. The data presented in this paper were obtained from the Mikulski Archive for Space Telescopes (MAST). The STScI is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555. Support for MAST for non-HST data is provided by the NASA Office of Space Science via grant NNX09AF08G and by other grants and contracts. This research has made use of data and services provided by the International Astronomical Union's Minor Planet Center. The authors are thankful for the hospitality of the Veszprem Regional Centre of the Hungarian Academy of Sciences (MTA VEAB), where part of this project was carried out. We are also thankful to our reviewers for their fair and balanced reports. AB - The K2 mission of the Kepler Space Telescope allowed the observations of light curves of small solar system bodies throughout the whole solar system. In this paper, we present the results of a collection of K2 trans-Neptunian object observations between campaigns C03 (2014 November-2015 February) and C19 (2018 August-September), which includes 66 targets. Due to the faintness of our targets, the detectability rate of a light-curve period is similar to 56%, notably lower than in the case of other small-body populations, like Hildas or Jovian Trojans. We managed to obtain light-curve periods with an acceptable confidence for 37 targets; the majority of these cases are new identifications. We were able to give light-curve amplitude upper limits for the other 29 targets. Several of the newly detected light-curve periods are longer than similar to 24 hr, in many cases close to similar to 80 hr; i.e., these targets are slow rotators. This relative abundance of slowly rotating objects is similar to that observed among Hildas, Jovian Trojans, and Centaurs in the K2 mission, as well as among main belt asteroids measured with the TESS space telescope. Trans-Neptunian objects show notably higher light-curve amplitudes at large (D greater than or similar to 300 km) sizes than found among large main belt asteroids, in contrast to the general expectation that due to their lower compressive strength, they reach hydrostatic equilibrium at smaller sizes than their inner solar system counterparts. LA - English DB - MTMT ER - TY - CONF AU - Kecskeméthy, Viktória AU - Kiss, Csaba AU - Szakáts, Róbert AU - Pál, András AU - Szabó M., Gyula AU - Molnár, László AU - Sárneczky, Krisztián AU - Vinkó, József AU - Szabó, Róbert AU - Marton, Gábor AU - Takácsné Farkas, Anikó AU - Kalup, Csilla AU - Kiss, L. László TI - Rotational properties of Kuiper belt objects as seen by the K2 mission T2 - 16th Europlanet Science Congress 2022 PY - 2022 DO - 10.5194/epsc2022-677 UR - https://m2.mtmt.hu/api/publication/33364891 ID - 33364891 AB - Earlier reviews of trans-Neptunian light curves reported mean rotation periods of P = 7-8 h (Duffard et al., 2009), and it was also found that the binary trans-Neptunian population rotates slower (Thirouin & Sheppard, 2014), and objects in the cold classical population have larger variability and rotate slower than the non-cold classical TNOs (Benecchi et al., 2013,Thirouin & Sheppard, 2019). While ground-based observations have obvious limitations in detecting long-period light curves the K2 mission of the Kepler Space Telescope allowed long (up to ~80 days), uninterrupted observations of many Solar system objects, including main belt asteroids, Hildas, Jovian trojans, and also the irregular satellites of giant planets. Light curves were also published for a few, selected trans-Neptunian objects based on K2 observations (see Kiss et al., 2020, for a summary). A common outcome of the studies of larger samples, across all dynamical classes, was the identification of an increased number of targets with long rotation periods compared to previous ground-based studies. A similar trend is observed among the data of nearly 10 000 main belt asteroids obtained by the TESS Space Telescope (Pál et al., 2020), and asteroids with long rotation periods were identified in other surveys like the Asteroid Terrestrial-impact Last Alert System (ATLAS), the Zwicky Transient Facility (Erasmus et al., 2021) and the All-Sky Automated Survey for Supernovae (Hanus et al., 2021). We have collected the K2 trans-Neptunian object observations between Campaigns C03 (November 2014 -- February 2015) to C19 (August -- September, 2018), which includes 67 targets. Due to the faintness of our targets the detectability rate of a light curve period is ~57 %, notably lower than in the case of other small body populations, like Hildas or Jovian trojans. We managed to obtain light curve periods with an acceptable confidence for 36 targets; the majority of these cases are new identifications. We were able to give light curve amplitude upper limits for the other 31 targets. Several of the newly detected light curve periods are longer than ~24 h, in many cases close to ~100 h, i.e., slow rotators.There is a very significant difference between the rotation rates of the LCDB and K2 TNO samples (Figs. 1 and 2). The mean LCD spin frequency is 2.71 c/d (8.8 h), while it is 0.87 c/d (27.6 h) in the K2 sample which is more similar to the K2 Hilda and Jovian Trojan spin frequency distrbutions. Thirouin & Sheppard (2019) obtained 9.48±1.53 h and 8.45±0.58 h mean rotation periods for the cold classical and the non-cold classical TNOs. Our mean values for the same dynamical groups (but using different targets) are notably longer: 1.21+1.58-0.63 c/d (19.83 h) and 0.83+1.81-0.23 c/d (P=28.91 h), respectively. The K2 mean frequency is higher than that of the K2 Jovian Trojans and Hildas, but we could not detect the very long period targets that were observed in these other K2 samples. Figure 1: frequency distribution of asteroids. The cyan, magenta, green and blue colours represent the TNOs in the LCDB and Jovian trojans, Hildas and TNOs from K2, respectively. Figure 2: Frequency as a function of absolute magnitude. Big circles with error bars mark the median values standard deviations for the different samples. The horizontal dashed lines mark the spin frequencies of fast, slow, and very slow rotators (Pravec et al., 2002). While there are only three objects with D>500 km in our sample, there are a number of objects -- both with and without detected light curve periods -- that fall in the 300≤D≤500 km transitional zone where asphericity -- hence light curve amplitude -- is expected to drop assuming a single rotating body, assuming main belt composition. Main belt asteroids are already almost extinct in this size range, and so are Centaurs -- for these bodies irregular shapes are expected in most cases. While the general trend is that larger objects have smaller light curve amplitudes among TNOs -- a trend followed both by our sample and the LCDB TNOs -- there are a considerable number of TNOs with high asphericity in the 300≤D≤500 km size range. This contradiction could be resolved if TNOs had higher-than-expected compressive strength and become spherical for sizes larger than their main belt counterparts, and remain 'irregular' in the 300≤D≤500 km range. However, their general low density and high porosity point against this scenario. A notable fraction of contact or semi-contact binary systems in which the members themselves are in hydrostatical equlibrium could produce a population of high-amplitude light curves in this size range (Lacerda et al., 2006, 2014). As some authors pointed out, contact binaries may be very frequent, especially in the plutino population (Thirouin & Sheppard, 2018,2019). The long term stability of such systems against their tidal evolution, however, should be investigated to answer the reliability of this assumption. Finally, spherical (rotationally flattened) bodies with large albedo variegations could also explain the observed amplitudes. While the general expectation in most TNO light curve studies was a double peak light curve, in our sample most light curves were found to be single-peak, after comparing the single-peak and double-peak solutions.Fgiure 3: Light curve amplitude versus the estimated size of the targets in our sample. The region between the vertical dashed lines mark the irregular-to-spherical transition size range in the main belt. Blue and red symbols mark the K2 targets and K2 upper limits, small grey symbols correspond to main belt asteroids. Large gray symbols represent the theoretical maximum light curve amplitudes the of large main belt objects if it was solely caused by the elongated shape of a body with homogeneous albedo. LA - English DB - MTMT ER - TY - JOUR AU - Moór, Attila AU - Ábrahám, Péter AU - Kóspál, Ágnes AU - Su, Kate Y. L. AU - Rieke, George H. AU - Vida, Krisztián AU - Cataldi, Gianni AU - Bódi, Attila AU - Sódorné Bognár, Zsófia AU - Cseh, Borbála AU - Csörnyei, Géza AU - Egei, Nóra AU - Farkas, Anikó AU - Hanyecz, Ottó AU - Ignácz, Bernadett AU - Kalup, Csilla AU - Könyves-Tóth, Réka AU - Kriskovics, Levente AU - Mészáros, László AU - Pál, András AU - Ordasi, András AU - Sárneczky, Krisztián AU - Seli, Bálint Attila AU - Sódor, Ádám AU - Szakáts, Róbert AU - Vinkó, József AU - Zsidi, Gabriella TI - Mid-infrared time-domain study of recent dust production events in the extreme debris disc of TYC 4209-1322-1 JF - MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY J2 - MON NOT R ASTRON SOC VL - 516 PY - 2022 IS - 4 SP - 5684 EP - 5701 PG - 18 SN - 0035-8711 DO - 10.1093/mnras/stac2595 UR - https://m2.mtmt.hu/api/publication/33108812 ID - 33108812 N1 - Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, Eötvös Loránd Research Network (ELKH), Konkoly-Thege Miklós út 15-17, Budapest, H-1121, Hungary CSFK, MTA Centre of Excellence, Konkoly Thege Miklós út 15-17, Budapest, H-1121, Hungary ELTE Eötvös Loránd University, Institute of Physics, Pázmány Péter sétány 1/A, Budapest, H-1117, Hungary Max-Planck-Institut für Astronomie, Königstuhl 17, Heidelberg, D-69117, Germany Department of Astronomy, Steward Observatory, The University of Arizona, Tucson, AZ 85721-0009, United States Department of Planetary Sciences, Lunar & Planetary Laboratory, The University of Arizona, 1629 E University Blvd, Tucson, AZ 85721-0092, United States National Astronomical Observatory of Japan, Osawa 2-21-1, , Tokyo, Mitaka, 181-8588, Japan Department of Astronomy, Graduate School of Science, The University of Tokyo, Tokyo, 113-0033, Japan MTA, CSFK, Lendület Near-Field Cosmology Research Group, Hungary MTA-ELTE, Lendület 'Momentum' Milky Way Research Group, Hungary Faculty of Informatics, Eötvös Loránd University, Pázmány Péter sétány 1/A, Budapest, H-1117, Hungary Department of Astronomy, Eötvös Loránd University, Pázmány Péter sétány 1/A, Budapest, H-1117, Hungary Department of Optics and Quantum Electronics, University of Szeged, Dóm tér 9, Szeged, H-6720, Hungary Export Date: 16 June 2023 CODEN: MNRAA Correspondence Address: Moór, A.; Konkoly Observatory, Konkoly-Thege Miklós út 15-17, Hungary; email: moor@konkoly.hu AB - Extreme debris discs are characterized by unusually strong mid-infrared excess emission, which often proves to be variable. The warm dust in these discs is of transient nature and is likely related to a recent giant collision occurring close to the star in the terrestrial region. Here we present the results of a 877 days long, gap-free photometric monitoring performed by the Spitzer Space Telescope of the recently discovered extreme debris disc around TYC 4209-1322-1. By combining these observations with other time-domain optical and mid-infrared data, we explore the disc variability of the last four decades, with particular emphasis on the last 12 years. During the latter interval the disc showed substantial changes, the most significant was the brightening and subsequent fading between 2014 and 2018 as outlined in WISE data. The Spitzer light curves outline the fading phase and a subsequent new brightening of the disc after 2018, revealing an additional flux modulation with a period of ~39 days on top of the long-term trend. We found that all these variations can be interpreted as the outcome of a giant collision that happened at an orbital radius of ~0.3 au sometime in 2014. Our analysis implies that a collision on a similar scale could have taken place around 2010, too. The fact that the disc was already peculiarly dust rich 40 years ago, as implied by IRAS data, suggests that these dust production events belong to a chain of large impacts triggered by an earlier even more catastrophic collision. LA - English DB - MTMT ER - TY - JOUR AU - Szabó, Zs. M. AU - Kóspál, Ágnes AU - Ábrahám, Péter AU - Park, Sunkyung AU - Siwak, Michal AU - Green, J. D. AU - Pál, András AU - Acosta-Pulido, J. A. AU - Lee, J. -E. AU - Ibrahimov, M. AU - Grankin, K. AU - Kovács, B. AU - Bora, Zs. AU - Bódi, Attila AU - Cseh, Borbála AU - Csörnyei, Géza AU - Dróżdż, Marek AU - Hanyecz, O. AU - Ignácz, B. AU - Kalup, Csilla AU - Könyves-Tóth, Réka AU - Krezinger, Máté AU - Kriskovics, Levente AU - Ogłoza, Waldemar AU - Ordasi, A. AU - Sárneczky, Krisztián AU - Seli, Bálint Attila AU - Szakáts, Róbert AU - Sódor, Ádám AU - Szing, A. AU - Vida, Krisztián AU - Vinkó, József TI - A Multi-epoch, Multiwavelength Study of the Classical FUor V1515 Cyg Approaching Quiescence JF - ASTROPHYSICAL JOURNAL J2 - ASTROPHYS J VL - 936 PY - 2022 IS - 1 SN - 1538-4357 DO - 10.3847/1538-4357/ac82f5 UR - https://m2.mtmt.hu/api/publication/33087067 ID - 33087067 N1 - Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, Eötvös Loránd Research Network (ELKH), Konkoly-Thege Miklós út 15-17, Budapest, 1121, Hungary CSFK, MTA Centre of Excellence, Konkoly Thege Miklós út 15-17., Budapest, H-1121, Hungary Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, Bonn, D-53121, Germany Scottish Universities Physics Alliance (SUPA), School of Physics and Astronomy, University of St Andrews, North Haugh, St Andrews, KY16 9SS, United Kingdom Eötvös Loránd University, Department of Astronomy, Pázmány Péter sétány 1/A, Budapest, 1117, Hungary Max Planck Institute for Astronomy, Königstuhl 17, Heidelberg, D-69117, Germany ELTE Eötvös Loránd University, Institute of Physics, Pázmány Péter sétány 1/A, Budapest, H-1117, Hungary Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, United States MIT Kavli Institute for Astrophysics and Space Research, 70 Vassar Street, Cambridge, MA 02109, United States Instituto de Astrofísica de Canarias, Avenida Vía Láctea, Tenerife, Spain Departamento de Astrofísica, Universidad de La Laguna, Tenerife, Spain School of Space Research, Kyung Hee University, 1732, Deogyeong-daero, Giheung-gu, Yongin-si, Gyeonggi-do, 17104, South Korea Institute of Astronomy, Russian Academy of Sciences, 48 Pyatnitskaya st., Moscow, 119017, Russian Federation Crimean Astrophysical Observatory, p/o Nauchny298409 MTA CSFK Lendület Near-Field Cosmology Research Group, 1121 Konkoly Thege Miklós út, Budapest, 15-17, Hungary MTA-ELTE Lendület “Momentum” Milky Way Research Group, Hungary Mount Suhora Astronomical Observatory, Cracow Pedagogical University, ul. Podchorazych 2, Kraków, 30-084, Poland Department of Optics & Quantum Electronics, University of Szeged, Dóm tér 9, Szeged, 6720, Hungary Cited By :1 Export Date: 15 February 2023 Correspondence Address: Szabó, Zs.M.; Konkoly Observatory, Konkoly-Thege Miklós út 15-17, Hungary; email: szabo.zsofia@csfk.org AB - Historically, FU Orionis-type stars are low-mass, pre-main-sequence stars. The members of this class experience powerful accretion outbursts and remain in an enhanced accretion state for decades or centuries. V1515 Cyg, a classical FUor, started brightening in the 1940s and reached its peak brightness in the late 1970s. Following a sudden decrease in brightness, it stayed in a minimum state for a few months, then started brightening for several years. We present the results of our ground-based photometric monitoring complemented with optical/near-infrared spectroscopic monitoring. Our light curves show a long-term fading with strong variability on weekly and monthly timescales. The optical spectra show P Cygni profiles and broad blueshifted absorption lines, common properties of FUors. However, V1515 Cyg lacks the P Cygni profile in the Ca II 8498 Å line, a part of the Ca infrared triplet, formed by an outflowing wind, suggesting that the absorbing gas in the wind is optically thin. The newly obtained near-infrared spectrum shows the strengthening of the CO bandhead and the FeH molecular band, indicating that the disk has become cooler since the last spectroscopic observation in 2015. The current luminosity of the accretion disk dropped from the peak value of 138 L ⊙ to about 45 L ⊙, suggesting that the long-term fading is also partly caused by the dropping of the accretion rate. LA - English DB - MTMT ER - TY - JOUR AU - Szabó M., Gyula AU - Pál, András AU - Szigeti, László AU - Sódorné Bognár, Zsófia AU - Bódi, Attila AU - Kalup, Csilla AU - Jäger, Zoltán AU - Kiss, L. László AU - Kiss, Csaba AU - Kovács, József AU - Marton, Gábor AU - Molnár, László AU - Plachy, Emese AU - Sárneczky, Krisztián AU - Szakáts, Róbert AU - Szabó, Róbert TI - Rotation periods and shape asphericity in asteroid families based on TESS S1-S13 observations JF - ASTRONOMY & ASTROPHYSICS J2 - ASTRON ASTROPHYS VL - 661 PY - 2022 PG - 10 SN - 0004-6361 DO - 10.1051/0004-6361/202142223 UR - https://m2.mtmt.hu/api/publication/32826398 ID - 32826398 N1 - ELTE Eötvös Lorand University, Gothard Astrophysical Observatory, Szombathely, Hungary MTA-ELTE Exoplanet Research Group, Szent Imre h. u. 112, Szombathely, 9700, Hungary Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, Eötvös Lorand Research Network (ELKH), Konkoly Thege Miklos ut 15-17, Budapest, 1121, Hungary MTA-ELTE Lendület Milky Way Research Group, Szent Imre h u 112, Szombathely, 9700, Hungary MTA CSFK Lendület Near-Field Cosmology Research Group, Budapest, Hungary ELTE Eötvös Lorand University, Institute of Physics, 1117 Pazmany Peter setany 1/A, Budapest, Hungary ELTE Eötvös Lorand University, Department of Astronomy, 1117 Pazmany Peter setany 1/A, Budapest, 1117, Hungary Sydney Institute for Astronomy, School of Physics A29, University of SydneyNSW 2006, Australia Export Date: 18 January 2023 CODEN: AAEJA AB - Here we present the analysis of the distribution of rotation periods and light curve amplitudes based on 2859 family asteroids in 16 Main Belt families based on 9912 TESS asteroid light curves in the TSSYS-DR1 asteroid light curve database. We found that the distribution of the light curve properties follow a family-specific character in some asteroid families, including the Hungaria, Maria, Juno, Eos, Eucharis, and Alauda families. While in other large families, these distributions are in general very similar to each other. We confirm that older families tend to contain a larger fraction of more spheroidal, low-amplitude asteroids. We found that rotation period distributions are different in the cores and outskirts of the Flora and Maria families, while the Vesta, Eos, and Eunomia families lack this feature. We also confirm that very fast spinning asteroids are close to spherical (or spinning top shapes), and minor planets rotating slower than approximate to 11 h are also more spherical than asteroids in the 4-8 h period range and this group is expected to contain the most elongated bodies. LA - English DB - MTMT ER - TY - JOUR AU - Csörnyei, Géza AU - Szabados, László AU - Molnár, László AU - Cseh, Borbála AU - Egei, N. AU - Kalup, Csilla AU - Kecskemethy, V AU - Könyves-Tóth, Réka AU - Sárneczky, Krisztián AU - Szakáts, Róbert TI - Study of changes in the pulsation period of 148 Galactic Cepheid variables JF - MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY J2 - MON NOT R ASTRON SOC VL - 511 PY - 2022 IS - 2 SP - 2125 EP - 2146 PG - 22 SN - 0035-8711 DO - 10.1093/mnras/stac115 UR - https://m2.mtmt.hu/api/publication/32725386 ID - 32725386 N1 - Funding Agency and Grant Number: Hungarian National Research, Development and Innovation Office (NKFIH) [K-129249, GINOP-2.3.2-15-2016-00003, KKP-137523]; Lendulet grant of the Hungarian Academy of Sciences [LP2018-7/2021]; New National Excellence Programs of the Ministry of Innovation and Technology [UNKP-20-2, UNKP-21-2] Funding text: We thank the referee for their useful comments that helped to improve this paper. The research was completed with the extensive use of PYTHON, along with the NUMPY (Harris et al. 2020), SCIPY (Virtanen et al. 2020), and ASTROPY (Astropy Collaboration 2018) modules, and with the R software (R Core Team 2020). Some of the data used in the article were made available to the community through the Exoplanet Archive on behalf of the KELT project team. This research made use of NASA's Astrophysics Data System (ADS). For the data search and retrieval the authors made extensive use of the Vizier, CDS, and Simbad websites of the Strasbourg astronomical Data Center (https://cds.u-strasbg.fr/).This work has made use of data from the European Space Agency (ESA) mission Gaia (https://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, https://www.cosmos.esa.int/web/gaia/dpac/consortium).Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement. We acknowledge with thanks the variable star observations from the American Association of Variable Star Observers International Database contributed by observers worldwide and used in this research. The research leading to these results has been supported by the Hungarian National Research, Development and Innovation Office (NKFIH) grants K-129249, GINOP-2.3.2-15-2016-00003, and ' Elvonal KKP-137523 (`SeismoLab'), and by the Lendulet LP2018-7/2021 grant of the Hungarian Academy of Sciences. Cs. K acknowledges the support provided from the ' UNKP-20-2 and ' UNKP-21-2 New National Excellence Programs of the Ministry of Innovation and Technology from the source of the National Research, Development and Innovation Fund. AB - Investigating period changes of classical Cepheids through the framework of O - C diagrams provides a unique insight to the evolution and nature of these variable stars. In this work, the new or extended O - C diagrams for 148 Galactic classical Cepheids are presented. By correlating the calculated period change rates with the Gaia EDR3 colours, we obtain observational indications for the non-negligible dependence of the period change rate on the horizontal position within the instability strip. We find period fluctuations in 59 Cepheids with a confidence level of 99 per cent, which are distributed uniformly over the inspected period range. Correlating the fluctuation amplitude with the pulsation period yields a clear dependence, similar to the one valid for longer period pulsating variable stars. The non-negligible amount of Cepheids showing changes in their O - C diagrams that are not or not only of evolutionary origin points towards the need for further studies for the complete understanding of these effects. One such peculiar behaviour is the large amplitude period fluctuation in short period Cepheids, which occurs in a significant fraction of the investigated stars. The period dependence of the fluctuation strength and its minimum at the bump Cepheid region suggests a stability enhancing mechanism for this period range, which agrees with current pulsation models. LA - English DB - MTMT ER - TY - JOUR AU - Gupta, Rahul AU - Gupta, S. AU - Chattopadhyay, T. AU - Lipunov, V AU - Castro-Tirado, A. J. AU - Bhattacharya, D. AU - Pandey, S. B. AU - Oates, S. R. AU - Kumar, Amit AU - Hu, Y-D AU - Valeev, A. F. AU - Minaev, P. Yu AU - Kumar, H. AU - Vinkó, József AU - Dimple, Dimple AU - Sharma, V AU - Aryan, A. AU - Castellon, A. AU - Gabovich, A. AU - Moskvitin, A. AU - Ordasi, A. AU - Pál, András AU - Pozanenko, A. AU - Zhang, B-B AU - Kumar, B. AU - Svinkin, D. AU - Saraogi, D. AU - Vlasenko, D. AU - Fernandez-Garcia, E. AU - Gorbovskoy, E. AU - Anupama, G. C. AU - Misra, K. AU - Sárneczky, Krisztián AU - Kriskovics, Levente AU - Castro-Tirado, M. A. AU - Caballero-Garcia, M. D. AU - Tiurina, N. AU - Balanutsa, P. AU - Lopez, R. R. AU - Sanchez-Ramirez, R. AU - Szakáts, Róbert AU - Belkin, S. AU - Guziy, S. AU - Iyyani, S. AU - Tiwari, S. N. AU - Vadawale, Santosh V. AU - Sun, T. AU - Bhalerao, V AU - Kornilov, V AU - Sokolov, V. V. TI - Probing into emission mechanisms of GRB 190530A using time-resolved spectra and polarization studies: synchrotron origin? JF - MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY J2 - MON NOT R ASTRON SOC VL - 511 PY - 2022 IS - 2 SP - 1694 EP - 1713 PG - 20 SN - 0035-8711 DO - 10.1093/mnras/stac015 UR - https://m2.mtmt.hu/api/publication/32720651 ID - 32720651 N1 - Aryabhatta Research Institute of Observational Sciences (ARIES), Manora Peak, Uttarakhand, Nainital, 263002, India Department of Physics, Deen Dayal Upadhyaya Gorakhpur University, Uttar Pradesh, Gorakhpur, 273009, India Department of Physics, Indian Institute of Technology Bombay, Powai, Maharashtra, Mumbai, 400076, India Inter-University Center for Astronomy and Astrophysics, Maharashtra, Pune, 411007, India Kavli Institute of Particle Astrophysics and Cosmology, Stanford University, 452 Lomita Mall, Stanford, CA 94305, United States Physics Department, Lomonosov Moscow State University, SAI, 13 Univeristetskij pr-t, Moscow, 119991, Russian Federation Instituto de Astrofísica de Andalucía (IAA-CSIC), Glorieta de la Astronomía s/n, Granada, E-18008, Spain Departamento de Ingeniería de Sistemas y Automática, Escuela de Ingenierías, Universidad de Málaga, C. Dr. Ortiz Ramos sn, Málaga, E-29071, Spain School of Physics and Astronomy, University of Birmingham, Birmingham, B15 2TT, United Kingdom School of Studies in Physics and Astrophysics, Pandit Ravishankar Shukla University, Chhattisgarh, Raipur, 492010, India Facultad de Ciencias Campus, Universidad de Granada, Fuentenue va s/n, Granada, E-18071, Spain Special Astrophysical Observatory of Russian Academy of Sciences, Nizhniy Arkhyz, 369167, Russian Federation Crimean Astrophysical Observatory, Russian Academy of Sciences, Nauchnyi298409, Russian Federation Space Research Institute, Russian Academy of Sciences, Profsoyuznaya ul. 84/32, Moscow, 117997, Russian Federation Lebedev Physical Institute, Leninsky Avenue 53, Moscow, 119991, Russian Federation Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, Konkoly Thege ut 15-17, Budapest, 1121, Hungary Institute of Physics, ELTE Eötvös Loránd University, Pázmány Péter Sétany 1/A, Budapest, 1117, Hungary Department of Optics and Quantum Electronics, University of Szeged, Dóm tér 9, Szeged, 6720, Hungary Department of Physics, KTH Royal Institute of Technology, AlbaNova, Stockholm, SE-10691, Sweden Facultad de Ciencias, Universidad de Málaga, Málaga, E-29010, Spain National Research University 'Higher School of Economics', Myasnitskaya 20, Moscow, 101000, Russian Federation School of Astronomy and Space Science, Nanjing University, Nanjing, 210093, China Key Laboratory of Modern Astronomy and Astrophysics (Nanjing University), Ministry of Education, Nanjing, 210093, China Ioffe Institute, 26, Politechnic Str, St Petersburg, 194021, Russian Federation Indian Institute of Astrophysics, II Block Koramangala, Karnataka, Bengaluru, 560034, India Instituto de Astrofísica de Canarias (IAC), Calle Vía Láctea s/n, La Laguna, Tenerife, E-38200, Spain INAF, Istituto di Astrofisica e Planetologia Spaziali, Via Fosso del Cavaliere 100, Rome, I-00133, Italy Nikolaev National University, Nikolska 24, Nikolaev, UA-54030, Ukraine Nikolaev Astronomical Observatory, Nikolaev, UA-54030, Ukraine Indian Institute of Science Education and Research, Kerala, Thiruvananthapuram, 695551, India Physical Research Laboratory, Navrangpura, Gujarat, Ahmedabad, 380009, India Purple Mountain Observatory, Academia Sinica, Nanjing, 210008, China Export Date: 6 April 2022 CODEN: MNRAA Correspondence Address: Gupta, R.; Aryabhatta Research Institute of Observational Sciences (ARIES), Manora Peak, Uttarakhand, India; email: rahulbhu.c157@gmail.com Correspondence Address: Pandey, S.B.; Aryabhatta Research Institute of Observational Sciences (ARIES), Manora Peak, Uttarakhand, India; email: shashi@aries.res.in Correspondence Address: Chattopadhyay, T.; Kavli Institute of Particle Astrophysics and Cosmology, 452 Lomita Mall, United States; email: tanmoyc@stanford.edu AB - Multipulsed GRB 190530A, detected by the Gamma-ray Burst Monitor (GBM) and Large Area Telescope onboard Fermi, is the sixth most fluent GBM burst detected so far. This paper presents the timing, spectral, and polarimetric analysis of the prompt emission observed using AstroSat and Fermi to provide insight into the prompt emission radiation mechanisms. The time-integrated spectrum shows conclusive proof of two breaks due to peak energy and a second lower energy break. Time-integrated (55.43 +/- 21.30 per cent) as well as time-resolved polarization measurements, made by the Cadmium Zinc Telluride Imager (CZTI) onboard AstroSat, show a hint of high degree of polarization. The presence of a hint of high degree of polarization and the values of low energy spectral index (alpha(pt)) do not run over the synchrotron limit for the first two pulses, supporting the synchrotron origin in an ordered magnetic field. However, during the third pulse, alpha(pt) exceeds the synchrotron line of death in few bins, and a thermal signature along with the synchrotron component in the time-resolved spectra is observed. Furthermore, we also report the earliest optical observations constraining afterglow polarization using the MASTER (P < 1.3 per cent) and the redshift measurement (z = 0.9386) obtained with the 10.4 m GTC (Gran Telescopio Canarias) telescopes. The broad-band afterglow can be described with a forward shock model for an ISM (interstellar medium)-like medium with a wide jet opening angle. We determine a circumburst density of n(0) similar to 7.41, kinetic energy E-K similar to 7.24 x 10(54) erg, and radiated gamma-ray energy E-gamma,E-iso similar to 6.05 x 10(54) erg. LA - English DB - MTMT ER - TY - JOUR AU - Wang, Qinan AU - Rest, Armin AU - Zenati, Yossef AU - Ridden-Harper, Ryan AU - Dimitriadis, Georgios AU - Narayan, Gautham AU - Villar, V. Ashley AU - Magee, Mark R. AU - Foley, Ryan J. AU - Shaya, Edward J. AU - Garnavich, Peter AU - Wang, Lifan AU - Hu, Lei AU - Bódi, Attila AU - Armstrong, Patrick AU - Auchettl, Katie AU - Barclay, Thomas AU - Barentsen, Geert AU - Sódorné Bognár, Zsófia AU - Brimacombe, Joseph AU - Bulger, Joanna AU - Burke, Jamison AU - Challis, Peter AU - Chambers, Kenneth AU - Coulter, David A. AU - Csörnyei, Géza AU - Cseh, Borbála AU - Deckers, Maxime AU - Dotson, Jessie L. AU - Galbany, Lluís AU - González-Gaitán, Santiago AU - Gromadzki, Mariusz AU - Gully-Santiago, Michael AU - Hanyecz, Ottó AU - Hedges, Christina AU - Hiramatsu, Daichi AU - Hosseinzadeh, Griffin AU - Howell, D. Andrew AU - Howell, Steve B. AU - Huber, Mark E. AU - Jha, Saurabh W. AU - Jones, David O. AU - Könyves-Tóth, Réka AU - Kalup, Csilla AU - Kilpatrick, Charles D. AU - Kriskovics, Levente AU - Li, Wenxiong AU - Lowe, Thomas B AU - Margheim, Steven AU - McCully, Curtis AU - Mitra, Ayan AU - Muñoz, Jose A. AU - Nicholl, Matt AU - Nordin, Jakob AU - Pál, András AU - Pan, Yen-Chen AU - Piro, Anthony L. AU - Rest, Sofia AU - Rino-Silvestre, João AU - Rojas-Bravo, César AU - Sárneczky, Krisztián AU - Siebert, Matthew R. AU - Smartt, Stephen J. AU - Smith, Ken AU - Sódor, Ádám AU - Stritzinger, Maximilian D. AU - Szabó, Róbert AU - Szakáts, Róbert AU - Tucker, Brad E. AU - Vinkó, József AU - Wang, Xiaofeng AU - Wheeler, J. Craig AU - Young, David R. AU - Zenteno, Alfredo AU - Zhang, KaiCheng AU - Zsidi, Gabriella TI - SN 2018agk: A Prototypical Type Ia Supernova with a Smooth Power-law Rise in Kepler (K2) JF - ASTROPHYSICAL JOURNAL J2 - ASTROPHYS J VL - 923 PY - 2021 IS - 2 SN - 1538-4357 DO - 10.3847/1538-4357/ac2c84 UR - https://m2.mtmt.hu/api/publication/32558149 ID - 32558149 LA - English DB - MTMT ER -