Cosmic Newsflash

ZTF catches a star devouring its own world

Kishalay, De et al.; Nature

For the first time, astronomers have caught a star in the act of swallowing a planet whole. The sun-like star, called ZTF SLRN-2020, lies about 12,000 light-years away in our galaxy and is thought to have engulfed a hot gas giant about the size of Jupiter.

Radio signals reveal origin of a supernova

Erik Kool et al, Nature

In the latest issue of the journal Nature, astronomers from the ZTF collaboration, based at the Stockholm University reveal the origin of a thermonuclear supernova explosion. Strong emission lines of helium and the first detection of such a supernova in radio waves show that the exploding white dwarf star had a helium-rich companion.

Press Release

Discovery of polars from a ZTF and eFEDS crossmatch

Rodriguez, Antonio C. et al.,

Magnetic cataclysmic variables have been hard to find purely in optical surveys because of the lack of outburst behavious. In this new study, authors crossmatch ZTF survey with the public eROSITA Final Equitorial Depth Survey (eFEDS) and find two new polars. Studying such objects can provide important information on how accretion takes place under the influence of strong magnetic fields.

Growth rate measurements using ZTF survey simulations

Carreres, Bastien et al.,

Measurements of the growth rate of structures at red shifts of less than 0.1 with peculiar velocity surveys have the potential of testing the validity of general relativity on cosmic scales. In this work, authors present growth-rate measurements from realistic simulated sets of type-Ia supernovae (SNe Ia) from the Zwicky Transient Facility (ZTF). The paper also describes the simulation methodology, the light-curve fitting and peculiar velocity estimation.

Tidal Disruption Event Demographics with the ZTF

Yao, Yuhan et al.,

In this paper, the authors conduct a systematic tidal disruption event (TDE) demographics analysis using the largest sample of optically selected TDEs. A flux-limited, spectroscopically complete sample of 33 TDEs is constructed using the Zwicky Transient Facility (ZTF) over three years (from October 2018 to September 2021). Authors also developed a survey efficiency corrected maximum volume method to infer the rates.

SN 2020jgb - yet another peculiar Type Ia supernova

Chen Z.H. et al.,

Thicker He-shells and less massive white dwarfs may explain some recently observed peculiar supernovae (SN) Type Ia. In this paper, the authors analyze SN 2020jgb, a peculiar SN Ia discovered by the Zwicky Transient Facility (ZTF). They find prominent absorption feature at ~1 μm in the near- infrared (NIR) spectrum of SN 2020jgb, consistent with the rest of peculiar He-shell double detonation (DDet) candidates discovered to date. SN 2020jgb was spotted in a star-forming dwarf galaxy, showing that He-shell DDet SNe occur in both star-forming and passive galaxies, consistent with the normal SN Ia population.

Studying SX Phoenicis variable stars with ZTF

Chow-Choong Ngeow et al.,

SX Phoenicis (SXP) variables are short-period pulsating stars that exhibit a period-luminosity (PL) relation. The authors derive the gri-band PL and extinction-free period-Wesenheit (PW) relations, as well as the period-color and reddening-free period-Q-index relations for 47 SXP stars located in 21 globular clusters, using the optical light curves from Zwicky Transient Facility.