St Andrews Research Repository

St Andrews University Home
View Item 
  •   St Andrews Research Repository
  • University of St Andrews Research
  • University of St Andrews Research
  • University of St Andrews Research
  • View Item
  •   St Andrews Research Repository
  • University of St Andrews Research
  • University of St Andrews Research
  • University of St Andrews Research
  • View Item
  •   St Andrews Research Repository
  • University of St Andrews Research
  • University of St Andrews Research
  • University of St Andrews Research
  • View Item
  • Login
JavaScript is disabled for your browser. Some features of this site may not work without it.

The MUSCLES Treasury Survey. IV. : Scaling relations for ultraviolet, Ca II K, and energetic particle fluxes from M dwarfs

Thumbnail
View/Open
Youngblood_2017_AJ_MUSCLES_FinalPubVersion.pdf (6.906Mb)
Date
28/06/2017
Author
Youngblood, Allison
France, Kevin
Loyd, R. O. Parke
Brown, Alexander
Mason, James P.
Schneider, P. Christian
Tilley, Matt A.
Berta-Thompson, Zachory K.
Buccino, Andrea
Froning, Cynthia S.
Hawley, Suzanne L.
Linsky, Jeffrey
Mauas, Pablo J. D.
Redfield, Seth
Kowalski, Adam
Miguel, Yamila
Newton, Elisabeth R.
Rugheimer, Sarah
Segura, Antigona
Roberge, Aki
Vieytes, Mariela
Keywords
Stars: chromospheres
Stars: low-mass
Sun: flares
QB Astronomy
QC Physics
3rd-DAS
Metadata
Show full item record
Altmetrics Handle Statistics
Altmetrics DOI Statistics
Abstract
Characterizing the UV spectral energy distribution (SED) of an exoplanet host star is critically important for assessing its planet's potential habitability, particularly for M dwarfs, as they are prime targets for current and near-term exoplanet characterization efforts and atmospheric models predict that their UV radiation can produce photochemistry on habitable zone planets different from that on Earth. To derive ground-based proxies for UV emission for use when Hubble Space Telescope (HST) observations are unavailable, we have assembled a sample of 15 early to mid-M dwarfs observed by HST and compared their nonsimultaneous UV and optical spectra. We find that the equivalent width of the chromospheric Ca ii K line at 3933 Å, when corrected for spectral type, can be used to estimate the stellar surface flux in ultraviolet emission lines, including H i Lyα. In addition, we address another potential driver of habitability: energetic particle fluxes associated with flares. We present a new technique for estimating soft X-ray and >10 MeV proton flux during far-UV emission line flares (Si iv and He ii) by assuming solar-like energy partitions. We analyze several flares from the M4 dwarf GJ 876 observed with HST and Chandra as part of the MUSCLES Treasury Survey and find that habitable zone planets orbiting GJ 876 are impacted by large Carrington-like flares with peak soft X-ray fluxes ≥10−3 W m−2 and possible proton fluxes ~102–103 pfu, approximately four orders of magnitude more frequently than modern-day Earth.
Citation
Youngblood , A , France , K , Loyd , R O P , Brown , A , Mason , J P , Schneider , P C , Tilley , M A , Berta-Thompson , Z K , Buccino , A , Froning , C S , Hawley , S L , Linsky , J , Mauas , P J D , Redfield , S , Kowalski , A , Miguel , Y , Newton , E R , Rugheimer , S , Segura , A , Roberge , A & Vieytes , M 2017 , ' The MUSCLES Treasury Survey. IV. Scaling relations for ultraviolet, Ca II K, and energetic particle fluxes from M dwarfs ' , Astrophysical Journal , vol. 843 , no. 1 , 31 . https://doi.org/10.3847/1538-4357/aa76dd
Publication
Astrophysical Journal
Status
Peer reviewed
DOI
https://doi.org/10.3847/1538-4357/aa76dd
ISSN
0004-637X
Type
Journal article
Rights
© 2017 The American Astronomical Society. All rights reserved. This work is made available online in accordance with the publisher’s policies. This is the final published version of the work, which was originally published at: https://doi.org/10.3847/1538-4357/aa76dd
Collections
  • University of St Andrews Research
URL
https://arxiv.org/abs/1705.04361
URI
http://hdl.handle.net/10023/11529

Items in the St Andrews Research Repository are protected by copyright, with all rights reserved, unless otherwise indicated.

Advanced Search

Browse

All of RepositoryCommunities & CollectionsBy Issue DateNamesTitlesSubjectsClassificationTypeFunderThis CollectionBy Issue DateNamesTitlesSubjectsClassificationTypeFunder

My Account

Login

Open Access

To find out how you can benefit from open access to research, see our library web pages and Open Access blog. For open access help contact: openaccess@st-andrews.ac.uk.

Accessibility

Read our Accessibility statement.

How to submit research papers

The full text of research papers can be submitted to the repository via Pure, the University's research information system. For help see our guide: How to deposit in Pure.

Electronic thesis deposit

Help with deposit.

Repository help

For repository help contact: Digital-Repository@st-andrews.ac.uk.

Give Feedback

Cookie policy

This site may use cookies. Please see Terms and Conditions.

Usage statistics

COUNTER-compliant statistics on downloads from the repository are available from the IRUS-UK Service. Contact us for information.

© University of St Andrews Library

University of St Andrews is a charity registered in Scotland, No SC013532.

  • Facebook
  • Twitter