Cosmological Applications of Novel Standardized Candles Andrew Friedman Thesis Advisor: : Robert Kirshner. Ramesh Narayan,, Chris Stubbs

Transcription

1 Cosmological Applications of Novel Standardized Candles Andrew Friedman Thesis Advisor: : Robert Kirshner Committee: : Lars Hernquist,, John Huchra, Ramesh Narayan,, Chris Stubbs Thesis Advisory Committee Meeting, June 26, 2006

2 Outline 1. Graduate School Timeline Milestones and Future Goals 2. PAIRITEL SN Project (Peters Automated Infrared Imaging Telescope) JHK Type Ia Light Curves Standard Candles? Data Collected, Light Curves, Data Analysis Issues Future Work 3. GRB Cosmology Project (NASA Swift satellite) Long Duration GRBs as Standardizable Candles Future Work: NASA GSRP Fellowship Project (Continuation of Research Exam Project) 4. ESSENCE Project Cosmology Analysis, Self-Calibration

3 PAIRITEL Project Research Collaborations CfA Supernova Group Robert Kirshner, Pete Challis, Malcolm Hicken, Andrew Friedman, Maryam Modjaz, W. Michael Wood-Vasey, Stephane Blondin Joshua Bloom (UC Berkeley), Cullen Blake (Harvard) GRB Cosmology With Swift Joshua Bloom (UC Berkeley), Neil Gehrels (NASA Goddard Space Flight Center)

4 Graduate School Timeline Entered Fall Now In 4 th year. Projected Graduation Date: Spring 2008 (or Fall 2009) On Medical Leave Fall Teaching Requirement Fulfilled, Spring Research Exam Completed, January 31, Thesis Advisor Chosen, April Thesis Proposal Submitted, October Courses Completed, February st TAC Meeting, June 26, 2006.

5 Publications & Presentations Publications Friedman, A. S. and Bloom, J. S. 2005, Towards a More Standardized Candle Using GRB Energetics and Spectra Astrophysical Journal, v627, Issue 1, pp (July 2005) Friedman A. S., and Bloom, J. S., 2005, "Present and Future Prospects for GRB Standard Candles", Il Nuovo Cimento C, v028, Issue 04-05, pp , (19 October 2005) Friedman, A. Using GRBs For Cosmology, Sky & Telescope, August 2006 (with Robert Naeye, Dissecting the Bursts of Doom, Sky & Telescope, August 2006 pp 30-37),Volume 112, No. 2, pg. 35 Presentations Selected PAIRITEL Data Analysis Issues, A.S. Friedman, 2 nd Annual PAIRITEL Workshop, Harvard-Smithsonian CfA, May 16, 2006 Infrared Light Curves of Nearby Supernovae with the Peters Automated Infrared Imaging Telescope (PAIRITEL), A.S. Friedman, M. Modjaz, W.M. Wood-Vasey, C.H. Blake, R.P. Kirshner, et al., 207th Meeting of the AAS, Washington, DC, Jan. 8-12, 2006 The Present and Future of GRB Cosmology, Friedman, A.S., Supernova Acceleration Probe (SNAP) Science Meeting, Lawrence Berkeley National Laboratories, Berkeley, CA, July 15, 2005 The Present and Future of GRB Cosmography, Friedman A.S., & Bloom, J.S., 205th Meeting of the AAS, San Diego, CA, Jan. 9-13, 2005 Towards a More Standardized Candle Using GRB Energetics and Spectra, Friedman A.S., & Bloom, J.S., 4 th Workshop on Gamma-Ray Bursts in the Afterglow Era, Rome, Italy, October 18-22, 2004

6 Fellowships, Honors & Awards National Aeronautics & Space Administration Graduate Student Research Program (NASA GSRP) Fellowship, 2006-present (NASA Goddard Space Flight Center, Greenbelt, Maryland) National Science Foundation (NSF) Graduate Research Fellowship, Certificate of Distinction in Teaching, Derek Bok Center for Teaching and Learning, Harvard University, Spring 2004, Fall 2005 Summer School in Astrostatistics, Penn State University, June 6-10, 2006.

7 PAIRITEL Supernova Project Andrew Friedman (Harvard-CfA CfA)

8 Outline : PAIRITEL SN Project 1. JHK Type Ia Light Curves Standard Candles? Science Motivations and Goals 2. Data Collected, Sample Light Curves 3. Data Analysis Issues 4. Future Work Maryam Modjaz : working on SNe Ib/c JHK data w/ PAIRITEL, GRB/SN connection Michael Wood-Vasey : also interested in SNe Ia in JHK

9 Advantages of Type Ia in JHK vs. UBVRI Type Ia SNe are standardizable candles at the ~0.18 mag level (MLCS2k2 method; Jha et. al 2005) JHK SNe Ia appear to be standard candles at the mag level or better (7-9% in distance), depending on the filter (Krisciunas et. al 2004, 2005) JHK LC s show no decline rate relations in the NIR (From < 20 JHK SNe Ia) (Krisciunas et. al 2004, 2005) JHK v.s. UBVRI mags have less systematic uncertainty due to dust extinction (A JHK < A V ) UBVRI + JHK = better determination of reddening A v (Krisciunas et. al 2006 in prep.) Reddening v.s. Wavelength

10 Other Groups Observing SNe in JHK The Carnegie Supernova Project Represents the main southern hemisphere competition to the nothern hemisphere PAIRITEL Supernova Project / CfA Supernova Program Largely complementary set of nearby supernovae in UBVRIJHK with a few overlapping SNe They have kindly published SNe Light Curves w/o galaxy templates on their website (We can compare overlapping SNe LC s and global properties of low-z sample)

11 Standard Candles in the NIR? Krisciunas et. al 2005 Krisciunas et. al 2005 Absolute mags of Type Ia SNe at max. light vs. the decline rate parameter m 15 (B) show a lack of decline rate relations and intrinsic scatter ~ mag in JHK. (Hubble diagram right)

12 JHK Utility for Reddening A v for SN2001el Krisciunas et. al 2006 in prep. SN2004S BVRIJHK LC s similar to LC s of SN2001el Measure A v, can learn about dust in highly extincted galaxy of 2001el For moderate amounts of extinction (~0.5 mag) we need rest frame optical and IR data to do a good job measuring the extinction A v and R v [A v /R v =E(B-V)]

13 Theoretical Models of NIR SNe Ia Theoretical models predict secondary maximum in JHK. Kasen astro-ph/ Effect is seen in observations for 2001el shown here (filled circles)

14 Theoretical Models of NIR SNe Ia Kasen astro-ph/ Intrinsically brighter SNe Ia have a later and more prominent secondary maximum in IJHK due to more 56 Ni mass produced.

15 Theoretical Models of NIR SNe Ia Peak H band mag is the best Type Ia standard candle. Kasen astro-ph/ Dots mark variation in 56 Ni mass produced ( M_sun). NIR SNe Ia should be standard candles at < ~0.2 mag level, despite varying 56 Ni mass.

16 Outline : PAIRITEL SN Project 1. JHK Type Ia Light Curves Standard Candles? Science Motivations and Goals 2. Data Collected, Sample Light Curves 3. Data Analysis Issues 4. Future Work

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20 PAIRITEL SN Data Census ( )

21 PAIRITEL SN Data Census ( )

22 Sample Light Curves

23 Sample Light Curves Michael Wood-Vasey

24 Outline : PAIRITEL SN Project 1. JHK Type Ia Light Curves Standard Candles? Science Motivations and Goals 2. Data Collected, Sample Light Curves 3. Data Analysis Issues 4. Future Work

25 J K (J H) Transformation, Mosaics J Band Mosaics: best quality Most images included in mosaic H Band Mosaics: good quality Most images included in mosaic Better than K, but worse than J K Band Mosaics: poorest quality In the past, sometimes fewer than half of images included in mosaic Why not use the J positions, relative image offsets to determine those for K (and H?)

26 J K (J H) Transformation, Mosaics

27 J K (J H) Transformation, Mosaics Relative Image to Image Transformation Equations Rotation Matrices

28 J K Transformation, Mosaics J K Offset Rotation Angle vs. Zenith Angle J H Offset Rotation Angle vs. Zenith Angle J K offsets independent of zenith angle J H offsets depend on zenith angle (flexure) Consistent with findings from 2MASS

29 Detecting Dither Problems Normal Dither Pattern Straying Dither Pattern PTEL Dither pattern problematic ~Feb 10-14, 2006 Multiple telescope control daemons conflicting

30 New Bad Pixel Masks 0.2% 1.2% 2.2% 2.5% 1.8% 2.3%

31 Priority Reduction Requests Web Page

32 Outline : PAIRITEL SN Project 1. JHK Type Ia Light Curves Standard Candles? Science Motivations and Goals 2. Data Collected, Sample Light Curves 3. Data Analysis Issues 4. Future Work

33 Future Work Obtain Remaining Template Images Reduce Data at Berkeley (Josh Bloom) Generate Light Curves First 2 Papers Plan (3-6 month timescale) (data paper + science paper) -Friedman, A., Wood-Vasey, W.M., Modjaz, M., Kirshner, R.P., Blake, C., Bloom, J.S. et al. Infrared Light Curves of Nearby Type Ia Supernovae with the Peters Automated Infrared Imaging Telescope (PAIRITEL) -Wood-Vasey, W.M., Friedman, A.S., Modjaz, M. Kirshner, R.P., Blake, C., Bloom, J.S. et al. The Absolute Brightness of Type Ia Supernovae in the Near Infrared

34 GRB Cosmology in the Swift Era Andrew Friedman (Harvard-CfA CfA)

35 GRB Redshifts Before and After Swift

36 Motivations: GRBs + SNe Ia GRBs: very bright; detectable out to z >2; both prompt-emission & afterglow (z~10-20?) -rays penetrate dust More tractable k-corrections Different evolution Different systematics Swift in space, JDEM: z max ~1.7 (Ia vs. Ib/c) GRB standard candles could serve as independent probes of cosmic expansion history, complementary to SNe Ia

37 Immediate Concerns Is high-z cosmology interesting? z > 1.7 is M -dominated No training set of nearby GRBs Few low-z GRBs High-z GRBs complement lower-z SNe Ia GRB coverage in 1<z<2 comparable to high-z SNe Ia from HST, 28 GRBs, ~28 High-z SNe (Knop et al. 2003, Riess et al. 2004, Riess et al. in prep) SNe Ia survey up to at least z ~ 2 crucial to pin down dark energy systematics (Linder & Huterer 2003) GRBs could constrain M, complementary to BAO, Galaxy Cluster constraints (best M prior?)

38 GRB Spectra: Band Model Smooth broken power Law (Band et al. 1993) Band Spectrum fits most bright BATSE GRBs (Preece et al. 2000) 4/12 GRB Spectra w/ z Amati et al Ep =Peak energy of F spectrum

39 GRB Energetics (Isotropic Equivalent) E iso distribution spans several orders of mag. E iso is a bad standard candle Fluence in observed bandpass Cosmological k-correction Luminosity Distance (theory) Hubble constant /70 kms -1 Mpc -1 Data from: Friedman & Bloom 2005 Redshift

40 GRB Jets & Beaming Beaming fraction f b inferred from achromatic break in afterglow light curve (t~t jet ) Top Hat Jet Model Stanek et. al 1999

41 Beaming Corrected Energy (E ) E distribution is much narrower than E iso (Frail et al. 2001, Piran et al. 2001, Bloom et al. 2003) the Frail Relation : E ~ constant 15 GRBs (f b ), 17 GRBs (z) Frail et al GRBs (f b ), 29 GRBs (z) Bloom et al. 2003

42 The Ep-E relation Friedman & Bloom 2005 The Ep-E relation plotted for a standard cosmology. Relation must be re-fit for each cosmology. Inset shows cosmology dependence of the slope of the relation. Note outliers and scatter.

43 GRB Hubble Diagram (Ep-E method - 19 GRBs) Friedman & Bloom 2005 GRB Hubble diagram for a standard cosmology before (right) and after (left) Ep-E correction. Note reduction in scatter. This plot must be re-calculated for every cosmology. Global 2 determines favored cosmology.

44 Sensitivity to Input Assumptions 2 2 = 3.71: upper left; triangle (Friedman & Bloom 2005) = 1.27: lower right; diamond (Ghirlanda et al. 2004c) Goodness of fit sensitive to: 1. n 2. n /n 3. Data set 4. References for individual GRBs 5. k-cor band (small # stats) n~1-2 cm -3 optimizes 2 Friedman & Bloom 2005b

45 Measuring the Necessary Observables To place a GRB on the E p -E relation, one needs to assume a cosmology, a k-cor bandpass, pick a model for the jet structure (i.e. E ), and measure the following (must at least have S, z, E p, & t jet ) : Fluence in observed bandpass (S ) Spectroscopic redshift (z) Peak of prompt-burst spectrum (E p ) Time of afterglow jet-break (t jet ) Ambient Density (n=10 cm -3?) -ray conversion efficiency ( =20%) EASY STANDARD HIT & MISS HARD VERY HARD UNKNOWN

46 Avoiding Sensitivity to Density, Efficiency Recent Work with Empirical Standard Candle with no Jet Model Assumptions: E iso ~ E p t jet (Liang & Zhang 2005, Xu 2005 ~ 2, ~ -1) Fluence in observed bandpass (S ) Spectroscopic redshift (z) Peak of prompt-burst spectrum (E p ) Time of afterglow jet-break (t jet ) Ambient Density (n=10 cm -3?) -ray conversion efficiency ( =20%) EASY STANDARD HIT & MISS HARD VERY HARD UNKNOWN

47 Other GRB Standardization Methods Previous GRB redshift indicators used prompt ray properties alone, using correlations found between isotropic luminosity (Liso) and Variability: Fenimore & Ramirez Ruiz 2000, Reichardt et. al 2001, Lloyd-Ronning & Ramirez-Ruiz, Firmani et. al 2006 Spectral Lags: Norris et. al 2000, Noriss 2002, Schaefer et. al 2001 Renewed enthusiasm for cosmographic utility of GRBs: Schaefer 2003, 2006, Takahashi 2003

48 Schaefer 2006 AAS GRB Hubble Diagram (5 methods combined 52 GRBs) Plot presentation is misleading. It ignores data dependence on the cosmology by only showing data points computed for Best Fit cosmology. Correct plot would also show data computed for Cosmological Constant cosmology. Only comparison of relative 2 can determine favored cosmology.

49 Dark Energy 2 Contours (5 methods combined 52 GRBs) Combining methods allows more GRBs to be placed on Hubble diagram, but obscures potential systematics. Most likely this is not evidence against but indirect evidence of GRB luminosity evolution with redshift. High z GRBs are higher luminosity due to lower metallicity progenitor stars and environments.

50 Sky & Telescope, August 2006 Issue

51 Simulations of Swift Data Bromm & Loeb 2002 Redshift distribution Flatness prior Mörtsell & Sollerman 2005 simulate sample of 200 Swift GRBs (Friedman & Bloom 2005) ~650 SNe Ia (Gold + SN Factory + ESSENCE) using SNOC package (Goobar et al. 2002) Bad News Without low-z sample (unlikely w/ Swift) GRBs alone sensitive to M, not GRBs insensitive to (w=w o ) or w(t) Good News LSS priors on M help SNe Ia, but similarly might be achieved w/ only standard candle techniques (GRB prior on M )

52 New Swift Bursts 163 GRBs localized since November 2004 launch 42 ground based follow up redshifts But z, E p, t jet not reliably measured by BAT, UVOT Less than 5 post-swift bursts can even be placed on the Ep-E relation (w/o upper or lower limits), and these were co-observed by other satellites (HETE-2, Integral) , a consistent w/ relation, for example In order for Swift to be a GRB cosmology satellite, new standardized candle relations in the data must be discovered

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54 Conclusions Good GRBs may constrain M best in future Complementary redshift distribution to SNe Ia Empirical approach avoids sensitivity to n, Bad No training set can t do, w, w(t) Lack of low-z coverage loitering problem Systematics, selection effects Lack of basis from physics Sample may only double in ~2 years Need Swift + HETE-2 + Integral +??? Even w/ training set, evolution degenerate w/ w(t)

55 Future Work: Systematic Errors Cosmological k-correction bandpass choice Neglecting Covariance Gravitational Lensing WIND vs. ISM Assuming the same density for all bursts Assuming the same efficiency for all bursts Selection Effects Nakar & Piran 2004, Band & Preece 2005

56 Future Work: NASA GSRP Compute Energetics, Jet Beaming Angles for Swift Bursts, compare pre & post Swift samples Search For Standardized Candle Correlations in Swift XRT X-Ray Afterglow Data GRB k-correction template spectra method Infer Spectral information for GRBs w/o measured spectra test Ep-Eiso, Ep-E relations Constrain Ultra High z GRB population with limits from Swift data

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58 Outreach Public Talks The Coolest Things In Astronomy: Take II, Guest Lecture, The Math Circle, Northeastern University, December Your Place in the Cosmos: From Planets to Stars to Galaxies and Beyond, Dudley House Crosstalk, Harvard University, December (With Mr. Ryan Hickox, Harvard-Smithsonian Center For Astrophysics) White Dwarfs, Neutron Stars, Black Holes, Supernova Explosions, and the Origins of Humanity, Guest Lecture, Science A-47: Cosmic Connections, Harvard University, November The Coolest Things In Astronomy, Guest Lecture, The Math Circle, Northeastern University, May Interviews Astronomy Q & A Podcast, Gamma-Ray Bursts (GRBs): A discussion with Robert Naeye & Andrew Friedman, Harvard-Smithsonian CfA Science Media Group, Interview with Robert Naeye, Senior Editor, Sky & Telescope Magazine, May Professor Robert Kirshner and I were interviewed at the 207th AAS Conference in Washington DC, Jan by Robert Irion of Science magazine. Irion, R., "Astronomers Push and Pull Over Dark Energy s Role in Cosmos", Science, 20 Jan. 2006, Vol. 311, pg. 316, (pdf) Professor Joshua Bloom and I were interviewed by Robert Irion of Science Magazine. Irion, R., "Astronomer's Eager for a Swift New Vision of the Universe", Science, 8 Oct. 2004, Vol. 306, pg

59 PAIRITEL Observations Statistics

60 PAIRITEL Project Statistics

61 Suggested Web Tools Web page with thumbnails of mosaic JPEGS. List of reduced/unreduced data Statistics for individual/all PAIRITEL projects Automated s sent to users with URL of such a page, notifications that data is ready Suggestions?

62 PAIRITEL SN Data Census (SN )

63 Master Table of GRB Observables RED = missing data Pre-Swift Post-Swift