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Weidong Li Jesse Leaman Alex Filippenko Department of Astronomy University of California, Berkeley Nearby Supernova Rates from the Lick Observatory Supernova.

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Presentation on theme: "Weidong Li Jesse Leaman Alex Filippenko Department of Astronomy University of California, Berkeley Nearby Supernova Rates from the Lick Observatory Supernova."— Presentation transcript:

1 Weidong Li Jesse Leaman Alex Filippenko Department of Astronomy University of California, Berkeley Nearby Supernova Rates from the Lick Observatory Supernova Search

2 Jesse Jesse Leaman Thesis work

3 Supernova Rates Cappellaro et al. 1999 (C99 hereafter) * 5 surveys (1 visual, 4 photographic plates) * 137 SNe in about 10 4 galaxies * B-band luminosity normalization * SN rate as a function of SN type (Ia, Ib/c, II) and host morphology (E/S0, Sa/b, Sbc/d, Irr) Mannucci et al. 2005 (M05 hereafter) Same database as C99 K-band luminosity normalization SNr versus galaxy color (B-K), mass Benchmark for z = 0 SN rate:

4 Lick Observatory, near San Jose, CA the Katzman Automatic Imaging Telescope; 0.76 m mirror.

5 The KAIT SN Search at Lick Obs. 1997: 1 (SN 1997bs) 1998: 20 (world record) 1999: 40 (world record) 2000: 38 (including SN 2000A) 2001: 68 (world record; SN 2001A) 2002: 82 (world record) 2003: 95 (world record) 2004: 83 2005: 82 2006: 84 2007: 69 2008: 32 http://astron.berkeley.edu/~bait/kait.html

6 LOSS results (1998-2006): Leaman, Li, & AVF (2008, in prep.) 844 SNe observed (600 LOSS discoveries & 240 independent confirmations) SNe used* in the SN rate calculation for a given normalization technique and SN type: Filter| Ia | Ib/c | II | ? | Total B 247 97 284 14 642 K 235 93 274 13 615 B&K 227 87 265 12 591 *Only SNe for which we have all host galaxy information were included

7 SN rate = No. of Supernovae ∑ L i x Monitoring_Time i i=1 15000 Rate calculation: Control time method KAIT/LOSS: snapshot (20 s, 7’x7’) images of individual nearby galaxies (~15000), not an all sky survey.

8 Control time (one epoch) d = 100 Mpc Mag limit = 19 Could see SN Ia for 80d, SN Ib/c for 35d, SN II-P for 110d (L08). L08 D=100Mpc Lim_mag = 19 110d

9 Control time (one epoch) L08: R band - 110d (SN II) C99: B band - 15d (SN II)

10 Observation interval (days) Number of observations 2001  2003 After June 2004 t1 t2 t3 7d14d CT=110d 110d Total ct = 110d + 7d +14d Obs intervals Control time (multi epochs) For SN Ia, 92% of the observations use the obs interval for the control time ~ a nearly continuous coverage!

11 Detailed log files The limiting magnitude was calculated for every single observation over the course of the survey. (Not done for previous nearby SN rate calculations.) Lmag = Lmag(intensity, FWHM, sky)

12 No clear inclination effect a) Ia Ibc II Face-on Inclined/edge-on Scd-Sm Sc Sbc Sb

13 Effect of peak mag and light curve shape Peak mag L08 vs C99 light curve +0.5 mag -0.5 mag

14 Radial distribution of LOSS SNe Survey completness a) We missed ~1% (5-10) of SNe near the galaxy nucleii. b) We missed very few SNe otherwise. Repeated survey with a small interval; Heavy SN search competition in these nearby galaxies

15 B-K color vs. inclination (B-K) color of highly inclined galaxies: may be affected by extinction. This effect needs to be corrected. (B-K) color and K mag are used to calculate the galaxy mass.

16 SN 2000bg NGC 6240 SN 2003ac IC 3203 SN 2001dc NGC 5777 SN 2002bx IC 2461 SN 2004bf UCG 08739 Top 10 “reddest” CC SN hosts SN 2002dq NGC 7051 SN 2003bk NGC 4316 SN 2000bs UGC 10710 SN 2005mg UGC 00155 SN 2006dp MCG-01-03-056

17 SN Ia rate - SNu(K) C99

18 SN Ibc rate - SNu(K) C99

19 SN II rate - SNu(K) C99

20 Volume SN Ia rate versus redshift L08 Z=0 0.34 ± 0.04 x 10 -4 (From SNuK only)

21 Conclusions Uncertainties are significantly reduced Increased number of SNe (~140 vs. ~600) No inclination correction factor CCD camera and image subtraction Limiting magnitude calculated for every obs SN rates normalized in K band: Nearly continuous search for SNe Ia: rates are not strongly affected by light curve shape and extinction For SNe Ibc and II, the impact of different peak mag for the chosen light curve can be easily quantified. The SN II light curve shape plays an important role in the rate calculation. The rates increase from early to late type galaxies for all three types of SNe.

22 Work in progress/Future refinements Finalizing rates normalized in B and mass More SN bins (e.g., IIn, IIb, II-P, II-L) Rates vs environment: cluster, AGN, radio More representative light curves (~1000 SNe have been monitored in the KAIT SN search unfiltered data: average light curve and luminosity function).

23 Katzman Automatic Imaging Telescope (KAIT) (Laurie Hatch)

24 Dependence of SN (Ia) rate on environment (work in progress) (Mannucci et al. In prep) a) Cluster versus field b) Radio properties c) Galaxy activities (AGN) Cluster (z=0.1) = 0.36 (+0.24-0.16) SNuB (Sharon et al. 2007) E/S0 (z=0) = 0.16 (0.05) SNuB (C99) E (z=0) = 0.182 (0.036) SNuB (LOSS) S0 (z=0) = 0.188 (0.032) SNuB (LOSS)


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