The University of Southampton
University of Southampton Institutional Repository
Warning ePrints Soton is experiencing an issue with some file downloads not being available. We are working hard to fix this. Please bear with us.

The eclipsing accreting white dwarf Z Chameleontis as seen with TESS

The eclipsing accreting white dwarf Z Chameleontis as seen with TESS
The eclipsing accreting white dwarf Z Chameleontis as seen with TESS
We present results from a study of TESS observations of the eclipsing dwarf nova system Z Cha, covering both an outburst and a superoutburst. We discover that Z Cha undergoes hysteretic loops in eclipse depth - out-of-eclipse flux space in both the outburst and the superoutburst. The direction that these loops are executed in indicates that the disk size increases during an outburst before the mass transfer rate through the disk increases, placing constraints on the physics behind the triggering of outbursts and superoutbursts. By fitting the signature of the superhump period in a flux-phase diagram, we find the rate at which this period decreases in this system during a superoutburst for the first time. We find that the superhumps in this source skip evolutionary stage "A" seen during most dwarf nova superoutbursts, even though this evolutionary stage has been seen during previous superoutbursts of the same object. Finally, O-C values of eclipses in our sample are used to calculate new ephemerides for the system, strengthening the case for a third body in Z Cha and placing new constraints on its orbit.
astro-ph.HE, astro-ph.SR
0035-8711
4149-4160
Court, J.M.C.
6e39b3e2-c269-49eb-9e06-cc47981117f1
Scaringi, S.
88701970-a1b9-41fe-bf55-886716ee3374
Rappaport, S.
26835e0d-eea2-4f54-9e16-ce12e5e6089d
Zhan, Z.
f23d16a6-80f8-453d-9df3-07a570e02dc9
Littlefield, C.
5844d5fc-231e-44dd-ab6f-ace3c7f92db7
Segura, N. Castro
26dfa223-df20-4ae1-98cc-7900dfe49fa3
Knigge, C.
ac320eec-631a-426e-b2db-717c8bf7857e
Maccarone, T.
c2f1d87b-e2ef-4e33-b09f-a2861d917ea8
Kennedy, M.
8affa89b-d733-4677-971d-c62804fcf49a
Szkody, P.
d5689046-e758-4f6c-9ba0-1e7083325f02
Garnavich, P.
a46bc21c-8239-423a-b02c-9cfd267b1a09
Court, J.M.C.
6e39b3e2-c269-49eb-9e06-cc47981117f1
Scaringi, S.
88701970-a1b9-41fe-bf55-886716ee3374
Rappaport, S.
26835e0d-eea2-4f54-9e16-ce12e5e6089d
Zhan, Z.
f23d16a6-80f8-453d-9df3-07a570e02dc9
Littlefield, C.
5844d5fc-231e-44dd-ab6f-ace3c7f92db7
Segura, N. Castro
26dfa223-df20-4ae1-98cc-7900dfe49fa3
Knigge, C.
ac320eec-631a-426e-b2db-717c8bf7857e
Maccarone, T.
c2f1d87b-e2ef-4e33-b09f-a2861d917ea8
Kennedy, M.
8affa89b-d733-4677-971d-c62804fcf49a
Szkody, P.
d5689046-e758-4f6c-9ba0-1e7083325f02
Garnavich, P.
a46bc21c-8239-423a-b02c-9cfd267b1a09

Court, J.M.C., Scaringi, S., Rappaport, S., Zhan, Z., Littlefield, C., Segura, N. Castro, Knigge, C., Maccarone, T., Kennedy, M., Szkody, P. and Garnavich, P. (2019) The eclipsing accreting white dwarf Z Chameleontis as seen with TESS. Monthly Notices of the Royal Astronomical Society, 488 (3), 4149-4160. (doi:10.1093/mnras/stz2015).

Record type: Article

Abstract

We present results from a study of TESS observations of the eclipsing dwarf nova system Z Cha, covering both an outburst and a superoutburst. We discover that Z Cha undergoes hysteretic loops in eclipse depth - out-of-eclipse flux space in both the outburst and the superoutburst. The direction that these loops are executed in indicates that the disk size increases during an outburst before the mass transfer rate through the disk increases, placing constraints on the physics behind the triggering of outbursts and superoutbursts. By fitting the signature of the superhump period in a flux-phase diagram, we find the rate at which this period decreases in this system during a superoutburst for the first time. We find that the superhumps in this source skip evolutionary stage "A" seen during most dwarf nova superoutbursts, even though this evolutionary stage has been seen during previous superoutbursts of the same object. Finally, O-C values of eclipses in our sample are used to calculate new ephemerides for the system, strengthening the case for a third body in Z Cha and placing new constraints on its orbit.

Text
1907.08458 - Accepted Manuscript
Download (1MB)

More information

Accepted/In Press date: 11 July 2019
e-pub ahead of print date: 31 July 2019
Published date: September 2019
Keywords: astro-ph.HE, astro-ph.SR

Identifiers

Local EPrints ID: 432968
URI: http://eprints.soton.ac.uk/id/eprint/432968
ISSN: 0035-8711
PURE UUID: c4c2b1b1-96f8-4a9a-8065-4527632824d3

Catalogue record

Date deposited: 05 Aug 2019 16:30
Last modified: 26 Nov 2021 06:52

Export record

Altmetrics

Contributors

Author: J.M.C. Court
Author: S. Scaringi
Author: S. Rappaport
Author: Z. Zhan
Author: C. Littlefield
Author: C. Knigge
Author: T. Maccarone
Author: M. Kennedy
Author: P. Szkody
Author: P. Garnavich

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×