Skip navigation
  • INAF logo
  • Home
  • Communities
    & Collections
  • Research outputs
  • Researchers
  • Organization units
  • Projects
  • Explore by
    • Research outputs
    • Researchers
    • Organization units
    • Projects
  • Login:
    • My DSpace
    • Receive email
      updates
    • Edit Account details
  • Italian
  • English

  1. OA@INAF
  2. PRODOTTI RICERCA INAF
  3. 1 CONTRIBUTI IN RIVISTE (Journal articles)
  4. 1.01 Articoli in rivista
Please use this identifier to cite or link to this item: http://hdl.handle.net/20.500.12386/28670
Title: Activity and rotation of the X-ray emitting Kepler stars
Authors: Pizzocaro, D.
STELZER, BEATE 
PORETTI, Ennio 
Raetz, S.
MICELA, Giuseppina 
Belfiore, A.
Marelli, M.
Salvetti, D.
DE LUCA, Andrea 
Issue Date: 2019
Journal: ASTRONOMY & ASTROPHYSICS 
Number: 628
First Page: A41
Abstract: The relation between magnetic activity and rotation in late-type stars provides fundamental information on stellar dynamos and angular momentum evolution. Rotation-activity studies found in the literature suffer from inhomogeneity in the measurement of activity indexes and rotation periods. We overcome this limitation with a study of the X-ray emitting, late-type main-sequence stars observed by XMM-Newton and Kepler. We measured rotation periods from photometric variability in Kepler light curves. As activity indicators, we adopted the X-ray luminosity, the number frequency of white-light flares, the amplitude of the rotational photometric modulation, and the standard deviation in the Kepler light curves. The search for X-ray flares in the light curves provided by the EXTraS (Exploring the X-ray Transient and variable Sky) FP-7 project allows us to identify simultaneous X-ray and white-light flares. A careful selection of the X-ray sources in the Kepler field yields 102 main-sequence stars with spectral types from A to M. We find rotation periods for 74 X-ray emitting main-sequence stars, 20 of which do not have period reported in the previous literature. In the X-ray activity-rotation relation, we see evidence for the traditional distinction of a saturated and a correlated part, the latter presenting a continuous decrease in activity towards slower rotators. For the optical activity indicators the transition is abrupt and located at a period of 10 d but it can be probed only marginally with this sample, which is biased towards fast rotators due to the X-ray selection. We observe seven bona-fide X-ray flares with evidence for a white-light counterpart in simultaneous Kepler data. We derive an X-ray flare frequency of 0.15 d<SUP>-1</SUP>, consistent with the optical flare frequency obtained from the much longer Kepler time-series.
URI: http://hdl.handle.net/20.500.12386/28670
URL: https://www.aanda.org/articles/aa/full_html/2019/08/aa31674-17/aa31674-17.html
https://arxiv.org/abs/1906.05587
ISSN: 0004-6361
DOI: 10.1051/0004-6361/201731674
Bibcode ADS: 2019A&A...628A..41P
Fulltext: open
Appears in Collections:1.01 Articoli in rivista

Files in This Item:
File Description SizeFormat 
1906.05587.pdfpostprint1.9 MBAdobe PDFView/Open
aa31674-17.pdfPdf editoriale2.19 MBAdobe PDFView/Open
Show full item record

Page view(s)

8
checked on Jan 26, 2021

Download(s)

5
checked on Jan 26, 2021

Google ScholarTM

Check

Altmetric


Items in DSpace are published in Open Access, unless otherwise indicated.


Explore by
  • Communities
    & Collections
  • Research outputs
  • Researchers
  • Organization units
  • Projects

Informazioni e guide per autori

https://openaccess-info.inaf.it: tutte le informazioni sull'accesso aperto in INAF

Come si inserisce un prodotto: le guide a OA@INAF

La Policy INAF sull'accesso aperto

Documenti e modelli scaricabili

Feedback
Built with DSpace-CRIS - Extension maintained and optimized by Logo 4SCIENCE