A survey for variable young stars with small telescopes: II -- Mapping a protoplanetary disk with stable structures at 0.15 AU
Creators: name: Evitts, Jack J.
name: Froebrich, Dirk
name: Scholz, Aleks
name: Eislöffel, Jochen
name: Campbell-White, Justyn
name: Furnell, Will
name: Urtly, Thomas
name: Pickard, Roger
name: Wiersema, Klaas
name: Dubovský, Pavol A.
name: Kudzej, Igor
name: Naves, Ramon
name: Aimar, Mario Morales
name: García, Rafael Castillo
name: Vanmunster, Tonny
name: Schwendeman, Erik
name: Alfaro, Francisco C. Soldán
name: Johnstone, Stephen
name: Farfán, Rafael Gonzalez
name: Killestein, Thomas
name: Casal, Jesús Delgado
name: de la Cuesta, Faustino García
name: Roberts, Dean
name: Kolb, Ulrich
name: Montoro, Luís
name: Licchelli, Domenico
name: Perez, Alex Escartin
name: Perez, Carlos Perelló
name: Deldem, Marc
name: Futcher, Stephen R. L.
name: Nelson, Tim
name: Dvorak, Shawn
name: Moździerski, Dawid
name: Quinn, Nick
name: Kotysz, Krzysztof
name: Kowalska, Katarzyna
name: Mikołajczyk, Przemysław
name: Fleming, George
name: Phillips, Mark
name: Vale, Tony
name: Dubois, Franky
name: Logie, Ludwig
name: Rau, Steve
name: Vanaverbeke, Siegfried
name: Merrikin, Barry
name: Mañanes, Esteban Fernández
name: Erdelyi, Emery
name: Carballo, Juan-Luis Gonzalez
name: Martinez, Fernando Limon
name: Long, Timothy P.
name: Delgado, Adolfo San Segundo
name: González, Josép Luis Salto
name: Espasa, Luis Tremosa
name: Piehler, Georg
name: Crumpton, James
name: Dover, Lord
name: Billington, Samuel J.
name: DArcy, Emma
name: Makin, Sally V.
name: Stecklum, Bringfried
Publisher: name: arXiv
Year: 2020
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences
subject: FOS: Physical sciences

description: The HOYS citizen science project conducts long term, multifilter, high cadence monitoring of large YSO samples with a wide variety of professional and amateur telescopes. We present the analysis of the light curve of V1490Cyg in the Pelican Nebula. We show that colour terms in the diverse photometric data can be calibrated out to achieve a median photometric accuracy of 0.02mag in broadband filters, allowing detailed investigations into a variety of variability amplitudes over timescales from hours to several years. Using GaiaDR2 we estimate the distance to the Pelican Nebula to be 870$^{+70}_{-55}$pc. V1490Cyg is a quasi-periodic dipper with a period of 31.447$\pm$0.011d. The obscuring dust has homogeneous properties, and grains larger than those typical in the ISM. Larger variability on short timescales is observed in U and R$_c-$H$α$, with U-amplitudes reaching 3mag on timescales of hours, indicating the source is accreting. The H$α$ equivalent width and NIR/MIR colours place V1490Cyg between CTTS/WTTS and transition disk objects. The material responsible for the dipping is located in a warped inner disk, about 0.15AU from the star. This mass reservoir can be filled and emptied on time scales shorter than the period at a rate of up to 10$^{-10}$M$_\odot$/yr, consistent with low levels of accretion in other T Tauri stars. Most likely the warp at this separation from the star is induced by a protoplanet in the inner accretion disk. However, we cannot fully rule out the possibility of an AA Tau-like warp, or occultations by the Hill sphere around a forming planet.
description: 27 pages, 17 figures, accepted by MNRAS, full version with full appendix available at http://astro.kent.ac.uk/~df/