Lessons Learned from Past/Ongoing Sky Survey Followup Paula Szkody University of Washington HotWiring V October 11, 2016

Survey Results (and Followup) depend on: Limiting magnitude (aperture needed) FOV (slit or multi-fiber) Filter(s) (other filters or spectra) Cadence (shorter) Timespan covered (longer) Data archive (immediate, easy access)

Past Useful Surveys (for CVs) Palomar-Green, 1.2m(P48), 10714 deg2, ~1976, [U-B color], B=16, 35 CVs Hamburg Survey,0.8m, 13600 deg2, 1985-97[prism],B=18.5, 140 CVs (53 new) FSVS, 2.5m, 23 deg2,1998-2001, [BVI], 22-24 mag – 2 CVs 2dF, 3.9m, 2 deg FOV, 740 deg2, 1998-2002, [spectra], B=21, ~21 CVs SDSS (APO) – 2.5m, 10 deg2 FOV, 14,500 deg2, 2002-2007+,[ugriz], g=21 DR9 release of Legacy, phot + spectra – 285 CVs (204 new) PanSTARRS1 (Haleakala) – 1.8m, 7 deg2 FOV, 2009-2014, 20.5 Data release 2016? 3pi + Medium Deep (60 epochs; 12x5 filters) Palomar Transient Factory (PTF) – 1.2m, 7.3 deg2 FOV, 2009-2012, [R,g], 20.5 phot+ spectra followup on 1.5m-10m – 344 CVs (66 new) DR1 released 2014 of selected fields DR2 released 2015 of all data DR3 release fall 2016 – light curves + more recent data

SDSS showed: Not all objects of interest are red e.g. CVs and WDs mostly blue but CV color range too wide for positive ID

Need follow-up spectra for ID and properties! Lesson learned from SDSS and PTF: polar polar Need follow-up spectra for ID and properties! polar IP Szkody et al. AJ 2002-2011 Papers I-VIII IP wd Groot et al, 2016

Computer + eye searches ID’d 285 CVs, 30 Polars, 6 IPs, 9 ZZ 2000-2011 followup phot+spect for Porb: ~ 100 nights APO (Szkody, Silvestri, Mukadam, etc) ~ 70 nights La Palma (Rodrigues-Gil,Gansicke et al.) ~ 100 nights USNO, UofA, MDM (Henden, Schmidt, Thorstensen, etc) 151 Periods determined then, ~175 now Lesson learned: it takes a lot of telescope time to get Porb!

Gansicke et al. 2009, MNRAS, 397, 2170 from 126 periods (disks) Prior to SDSS SDSS results Gansicke et al. 2009, MNRAS, 397, 2170 from 126 periods (disks)

Spectral Followup of systems found by CRTS ( Woudt et al Spectral Followup of systems found by CRTS ( Woudt et al. 2012, Thorstensen & Skinner 2012, Szkody et al. 2014 ) V=17-19 Gemini GMOS followup of 19-22 mag CRTS sources in SDSS –Breedt et al. 2014 Large telescopes are necessary for many current survey followups! 8m – 45 min exposures

Ongoing Surveys Intermediate Palomar Transient Factory (iPTF): 2013-2017 SkyMapper (Australia) : 1.35m, 5.7 deg2 FOV, 2012-2017, [uvgriz] Catalina Real-Time Transient Survey (CRTS): Mt. Lemmon 1.5m, Catalina 0.7m, Siding Springs 0.5m, 2004- ASAS (Pojmanski), MASTER (Lipunov): ASAS-SN (AssassinxOhio):4-14cm N&S all sky – 20,000 deg2/night, ASAS-SN Transients, ASAS-SN CV Patrol web pages, 1997- , MASTER-SAAO, 2014- Gaia:1.5x0.5m, 2013-2018 1 billion stars X 70 epochs, 20 mag K2: 100 deg2 FOV for 80 days, K2-K7 in MAST, 2014-2018, ongoing data releases LAMOST: 4m, 5deg FOV, 2011-2017, [spectra] DR1 of pilot 2012

Catalina Real-Time Transient Survey(CRTS) Mt. Lemmon 1.5m(MLS), Catalina 0.7m(CSS), Siding Springs 0.5m(SSS) 1350 CVs by outburst Drake et al. 2009-2014 Lesson learned: easy immediate web access is productive! Most are faint

Gaia Marshall

K2 Fields 60 CVs observed so far-K2-11 in progress Long cadence = 30 min Short cadence = 1 min 60 CVs observed so far-K2-11 in progress

K2-6 HS Vir Asymmetric=outside in, higher Mdot Higher Mdot Symmetric =inside out, low Mdot ?

K2-3 Intermediate Polar FO Aqr 1 day of SC observations Porb = 4.85 hr Pspin = 20.9 min

Bell et al. 2016 New outbursting WD in Kepler

Lesson learned: cadence and length of dataset matter ! Low Mdot High Mdot CRTS detecting outbursts Lesson learned: cadence and length of dataset matter !

Future Surveys ZTF 2017-2020 PanSTARRS2- 2017? LSST 2022-2032

ZTF 2017-2020 47 deg2 FOV on 1.2m, 20.5 mag 2 community surveys: Northern Sky Survey at 3 day cadence Galactic Plane Survey: 288/yr |b|< 7 deg; dec>-30 Summer schools in August (Caltech) + workshop at 2017 Jan AAS meeting Texas

ZTF will use P48 + P60 + 200 in for followup Survey optimized for existing telescope followup!

LSST 2022-2032 Southern Sky Survey, 8.4m, 9.6 deg2 FOV, 25,000 deg2, 30 min + 3 day cadence, ugrizy, ~800 images/object, 10 million alerts/night Deep Drilling Fields

Organizational Needs: Manage broker lists to identify interesting candidates for followup Worldwide followup consortia to narrow list thru low res spectra; organize followup Arrange multiwavelength TOO – UV (HST?), X-ray, Gamma-ray (Swift), radio (VLA)

Multiwavelength Obs of VW Hyi Wheatley et al. 1996 Multiwavelength Obs of VW Hyi

Summary of what works colors are useful for some prelim classification spectra are needed for positive ID, detailed classification prompt alerts/display of candidates allows max access coordination of telescopes, observers for subgroups feedback display of followup prevents duplication specific plans for long term followup coordinated TACs for multiwavelength efficiency

Some problem areas proper size of working groups software vs science groups access to good data products keeping records current