The Zwicky Transient Facility: Science Objectives

Graham, M. J.; Kulkarni, S. R.; Bellm, Eric C.; Adams, S. M.; Barbarino, C.; Blagorodnova, N.; Bodewits, Dennis; Bolin, Bryce; Brady, P. R.; Cenko, S. Bradley; Chang, Chan-Kao; Coughlin, M. W.; De, Kishalay; Eadie, Gwendolyn; Farnham, T. L.; Feindt, U.; Franckowiak, A.; Fremling, C.; Gezari, Suvi; Ghosh, S.; Goldstein, Daniel A.; Golkhou, V. Z.; Goobar, A.; Ho, Anna Y. Q.; Huppenkothen, Daniela; Ivezić, Željko; Jones, R. Lynne; Jurić, Mario; Kaplan, David L.; Kasliwal, M. M.; Kelley, Michael S. P.; Kupfer, Thomas; Lee, Chien-De; Lin, Hsing Wen; Lunnan, R.; Mahabal, A.; Miller, A. A.; Ngeow, Chow-Choong; Nugent, P.; Ofek, E. O.; Prince, Thomas A.; Rauch, L.; Roestel, Jan van; Schulze, S.; Singer, L. P.; Sollerman, J.; Taddia, F.; Yan, Lin; Ye, Quanzhi; Yu, Po-Chieh; Barlow, Tom A.; Bauer, J.; Beck, R.; Belicki, Justin; Biswas, Rahul; Brinnel, V.; Brooke, T. Y.; Bue, Brian D.; Bulla, Mattia; Burruss, Rick; Connolly, Andrew J.; Cromer, John; Cunningham, Virginia; Dekany, Richard; Delacroix, Alex; Desai, Vandana; Duev, Dmitry A.; Feeney, Michael; Flynn, David M.; Frederick, Sara; Gal‐Yam, A.; Giomi, M.; Groom, Steven L.; Hacopians, Eugean; Hale, David; Hélou, G.; Henning, John; Hover, David; Hillenbrand, Lynne A.; Howell, Justin; Hung, T.; Imel, D.; Ip, Wing-Huen; Jackson, E. S.; Kaspi, S.; Kaye, Stephen B.; Kowalski, M.; Kramer, Emily; Kuhn, Michael A.; Landry, Walter; Laher, Russ R.; Mao, Peter H.; Masci, Frank J.; Monkewitz, S.; Murphy, Patrick J.; Nordin, J.; Patterson, Maria T.; Penprase, Bryan E.; Porter, Michael; Rebbapragada, Umaa; Reiley, Dan; Riddle, Reed; Rigault, M.; Rodríguez, Héctor; Rusholme, B.; Santen, J. V.; Shupe, D. L.; Smith, Roger M.; Soumagnac, Maayane T.; Stein, R.; Surace, J.; Szkody, Paula; Terek, Scott; Sistine, Angela Van; Velzen, S. van; Vestrand, W. T.; Walters, Richard; Ward, Charlotte; Zhang, Chaoran; Zolkower, Jeffry

doi:10.1088/1538-3873/ab006c

Cited by 583 publications

(390 citation statements)

References 305 publications

Supporting

Mentioning

389

Contrasting

Order By: Relevance

“…As part of the Zwicky Transient Facility (ZTF), the Palomar 48-inch (P48) telescope images the sky every clear night (Bellm et al 2019a;Graham et al 2019). ZTF J2130+4420 was first discovered in a dedicated high-cadence survey at low Galactic latitudes performed in the ZTF-r band (Bellm et al 2019b).…”

Section: Observationsmentioning

confidence: 99%

The First Ultracompact Roche Lobe–Filling Hot Subdwarf Binary

Kupfer

Bauer

Marsh

et al. 2020

ApJ

Self Cite

View full text Add to dashboard Cite

We report the discovery of the first short period binary in which a hot subdwarf star (sdOB) fills its Roche lobe and started mass transfer to its companion. The object was discovered as part of a dedicated high-cadence survey of the Galactic Plane named the Zwicky Transient Facility and exhibits a period of P = 39.3401(1) min, making it the most compact hot subdwarf binary currently known. Spectroscopic observations are consistent with an intermediate He-sdOB star with an effective temperature of T eff = 42, 400 ± 300 K and a surface gravity of log(g)= 5.77 ± 0.05. A high-signal-to noise GTC+HiPERCAM light curve is dominated by the ellipsoidal deformation of the sdOB star and an eclipse of the sdOB by an accretion disk. We infer a low-mass hot subdwarf donor with a mass M sdOB = 0.337 ± 0.015 M and a white dwarf accretor with a mass M WD = 0.545 ± 0.020 M .Theoretical binary modeling indicates the hot subdwarf formed during a common envelope phase when a 2.5 − 2.8 M star lost its envelope when crossing the Hertzsprung Gap. To match its current P orb , T eff , log(g), and masses, we estimate a post-common envelope period of P orb ≈ 150 min, and find the sdOB star is currently undergoing hydrogen shell burning. We estimate that the hot subdwarf will become a white dwarf with a thick helium layer of ≈ 0.1 M and will merge with its carbon/oxygen white dwarf companion after ≈ 17 Myr and presumably explode as a thermonuclear supernova or form an R CrB star.

show abstract

Section: Observationsmentioning

confidence: 99%

The First Ultracompact Roche Lobe–Filling Hot Subdwarf Binary

Kupfer

Bauer

Marsh

et al. 2020

ApJ

Self Cite

View full text Add to dashboard Cite

show abstract

“…The Zwicky Transient Facility (ZTF) Graham et al 2019;Masci et al 2019) is currently surveying the entire northern sky, including dense Galactic plane fields. Here, we present preliminary results of the search for gravitational microlensing events in the ZTF data collected from the beginning of the survey (March 20, 2018) through June 30, 2019.…”

mentioning

confidence: 99%

Gravitational Microlensing Events from the First Year of the Northern Galactic Plane Survey by the Zwicky Transient Facility

et al. 2020

Self Cite

View full text Add to dashboard Cite

Note-HJD =HJD−2450000. Microlensing point-source point-lens models have the following parameters: t0 and u0 -time and separation during the closest approach between the lens and the source, tE -Einstein timescale, πE,N and πE,E -North and East components of the microlensing parallax vector, rs -r-band brightness of the source, fs -blending parameter. t0,par defines the coordinate system for parallax measurements and is not a fit parameter.

show abstract

“…Using the IRSA 10 catalogue and time series tool, ZTF DR1 (Bellm et al 2019a,b;Graham et al 2019) with over 50 epochs in g and r bands, no variability is observed by either the UCWD or the M dwarf. Cross-correlations of the 3 up-sampled medium resolution spectra show shifts of 0.022 pixels between the first and second epoch and −0.004 pixels between the second and third epoch.…”

Section: Unseen Companion(s)mentioning

confidence: 99%

First discovery of an ultra-cool white dwarf benchmark in common proper motion with an M dwarf

Lam

Hambly

Lodieu

et al. 2020

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

Ultra-cool white dwarfs are among the oldest stellar remnants in the Universe. Their efficient gravitational settling and low effective temperatures are responsible for the smooth spectra they exhibit. For that reason, it is not possible to derive their radial velocities or to find the chemistry of the progenitors. The best that can be done is to infer such properties from associated sources, which are coeval. The simplest form of such a system is a common proper motion pair where one star is an evolved degenerate and the other a main sequence star. In this work we present the discovery of the first of such a system, the M dwarf LHS 6328 and the ultra-cool white dwarf PSO J1801+625, from the Pan-STARRS 1 3π survey and the Gaia Data Release 2. Follow-up spectra were collected covering a usable wavelength range of 3750 to 24500Å. Their spectra show that the white dwarf has an effective temperature of 3550 K and surface gravity of log g = 7.45 ± 0.13 or log g = 7.49 ± 0.13 for a CO or He core, respectively, when compared against synthetic spectra of ultra-cool white dwarf atmosphere models. The system has slightly sub-solar metallicity with −0.25 < [Fe/H] < 0.0, and a spatial velocity of (U, V, W) = (−114.26 ± 0.24, 222.94 ± 0.60, 10.25 ± 0.34) km s −1 , the first radial velocity and metallicity measurements of an ultra-cool white dwarf. This makes it the first and only benchmark of its kind to date.

show abstract

The Zwicky Transient Facility: Science Objectives

Cited by 583 publications

References 305 publications

The First Ultracompact Roche Lobe–Filling Hot Subdwarf Binary

The First Ultracompact Roche Lobe–Filling Hot Subdwarf Binary

Gravitational Microlensing Events from the First Year of the Northern Galactic Plane Survey by the Zwicky Transient Facility

First discovery of an ultra-cool white dwarf benchmark in common proper motion with an M dwarf

Contact Info

Product

Resources

About