BE VERY AFRAID

Cosmologia en la Playa 2010 Supernovae and the Accelerating Universe Nicholas B. Suntzeff Mitchell Institute for Fundamental Physics & Astronomy Department of Physics & Astronomy Texas A&M University University of Texas/Austin 14 January 2010

How cosmology used to be done: Historical Visit of Einstein to Mt. Wilson Al Einstein  George Ellery Hale Ed Hubble Milt Humason Chuck St. James Walt Adams  lots of books

The sad reality of cosmology today: Unhistorical Visit of Suntzeff to Mt. Wilson Suntzeff Gaston Folatteli Mark Phillips  George Ellery Hale Same books =>

can’t get no respect…

SN1994D Supernovae! P. Challis CfA & NASA

SN spectra Type Ia Core Collapse Type Ib/c & Type II

SN SEDs Ia Ib/c II

General light curves 56 Ni  56 Co  56 Fe Leibundgut & Suntzeff 98

delta m15 Suntzeff (1996) Phillips (1993) Calan/Tololo survey One parameter family Color Rate of decline Peak brightness

Secondary max due to Fe ++  Fe + mystery - where is Fe +  Fe 0 ??

Absolute magnitudes of Type Ia SNe H, K probable standard candles, Krisciunas etal   brighter

Effects of correction to  m 15

brighter fainter 0.2 mag Peak effect for L is at about z~0.8. We are looking for about a 0.25m effect. Distance Modulus II

Equation-of-State Signal Difference in apparent SN brightness vs. z Ω Λ =0.70, flat cosmology Assume P = w  c 2

The Basic Question: Is a cosmological constant model consistent with the data? Is w=-1?

The ESSENCE Survey Determine w to 10% or w!=-1 6-year project on CTIO/NOAO 4m telescope in Chile; 12 sq. deg. Wide-field images in 2 bands Same-night detection of SNe Spectroscopy Keck, VLT, Gemini, Magellan Goal is 200 SNeIa, 0.2<z<0.8 Data and SNeIa public real-time

ESSENCE Survey Team Claudio AguileraCTIO/NOAOBruno LeibundgutESO Andy BeckerUniv. of WashingtonWeidong LiUC Berkeley Stéphane BlondinHarvard/CfAThomas MathesonNOAO Peter ChallisHarvard/CfAGajus MiknaitisFermilab Ryan ChornockUC BerkeleyJose PrietoOSU Alejandro ClocchiattiUniv. Católica de ChileArmin RestNOAO/CTIO Ricardo CovarrubiasUniv. of WashingtonAdam RiessSTScI/JHU Tamara DavisDark Cosmology CenterBrian SchmidtANU/Stromo/SSO Alex FilippenkoUC BerkeleyChris SmithCTIO/NOAO Arti GargHarvard UniversityJesper SollermanStockholm Obs. Peter GarnavichNotre Dame UniversityJason SpyromilioESO Malcolm HickenHarvard UniversityChristopher StubbsHarvard University Saurabh JhaSLAC/KIPACNicholas SuntzeffTexas A&M Robert KirshnerHarvard/CfAJohn TonryUniv. of Hawaii Kevin KrisciunasTexas A&MMichael Wood-VaseyHarvard/CfA

ESSENCE Summary 200 SNeIa from good light curves (Wood-Vasey, et al 2009) Data from Keck, Gemini, VLT, CTIO, HST

Gold  Union  Constitution  what the **** set SDSS SN plot Lesson in plotting  Being from Texas, I suggest the Confederate Set is next

Carnegie Supernova Project Phillips, Freedman, Hamuy, Madore, Burns, Follatelli, Cadenas, Suntzeff

High-z project I-band measurements

Cosmology fits

Carnegie Low-z Sample 5-year project, 270n per year on 1m Swope + nights on Magellan, du Pont, VLT Ending 2009 (around now) ugriBVYJH(K s ). K s with WIRC on duPont Spectra where we can [more hot spectrographs on 2m telescopes are needed] Follow all types with z≤0.08 (if caught early) 200 Sne with 100 Type Ia

What we are trying to do So many data samples with so many methods of analysis have confused us We want to “rewrite” history, that is, start with a clean data set and redo our analyses to find the weaknesses of our techniques. Purely phenomenological guided by simple physics Basic parameter -  m 15, measured from the light curves, NOT from a black box program Measure photometry in the natural system with measured precise transmission functions Ultimately the goal is an accuracy of <1% in distance for cosmology with no systematics.

Summary of Sample

First Release Contreras, C. et al 2009 arXiv: V1 35 Type Ia, 5559 ugriBV optical , 1043 NIR YJHK s 

Natural System  Definition of photometric zero-points

Second Parameter Same  m 15

The secondary maximum is not tightly correlated with the peak luminosity. Bolometric light curves

Reddening R V = 1.7 or 3.1?? Wang, Goobar suggestion

Distances to 3%

Hubble Diagram  z=0.001  m=0.12

Hicken et al 2009

A difficult diagram to understand 2  separation between blue and orange points??

Flux calibrations Bias in distance determination codes Extinction Host galaxy Our Galaxy Atmosphere Extinction law Passband errors K corrections Photometry normalization Nonlinearity in flux measurements Potential sources of systematic error

More Potential Systematics “Hubble bubble” trouble “Hubble bubble” trouble Gravitational lensing Gravitational lensing Evolutionary effects in SNe Evolutionary effects in SNe Biases in low redshift sample Biases in low redshift sample Search efficiency/selection Search efficiency/selection

(Wood-Vasey et al., 2007, ApJ)

Photometric Calibration Critical! 3% absolute offset in overall ZP with respect to nearby SNIa sample Dzp = 0.03 => Dw = % relative offset in color ZP Dcolor = 0.03 => Dw = 0.10 (Dw = change in the marginalized mean value of w)

SNe and GRB’s Wright (2007)

Higher-Z SN Team Riess, et al (2007)

Summary The accelerating Universe poses a significant challenge to theory, experiment and observation. Current goal: w to 10% The SNIa data are consistent with a flat Universe with a cosmological constant.

Closing thoughts The scale of dark matter DETF and future measures of dark energy The Hubble constant Why are we wasting our time with w’??? Why are there only 4 techniques? We need people to create realistic error models.

Okay, no questions Come up to the front, leave your computers behind, and let’s talk what it means to be a successful researcher.

(ESA) (JAXA) (ESA)

46 Astrophysics Division Missions

Assumed operating missions beyond 2016 include JWST, SOFIA HST De-orbit mission development ramps up ~2020 “Future Missions” wedge would be used for new mission initiatives, R&A/technology augmentations, extended missions, etc. The amount of “Future Missions” funding available between 2013 – 2020 is ~$4B Budget Guidance for Decadal Survey

Assumed operating missions beyond 2016 include JWST, SOFIA; plus HST, Chandra, Fermi, etc. (e.g., Astro-H) HST De-orbit mission development ramps up ~2020 “Future Missions” wedge is for strategic missions recommended by the Astro2010 decadal survey The amount of “Future Missions” funding available between 2013 – 2020 in such a scenario would be ~$2.3B Budget Guidance for Decadal Survey – Notional scenario

160 PhD’s per year, 35 permanent positions per year NASA science sees declining budgets NSF at best is flat DOE may step in? Job register has ~100 postdocs and ~16 faculty positions US budget is now heavily encumbered with future payments Obama loves science, but don’t assume that will go to basic science except in green and health science you probably will not live where you want to live The bad news

The good news everyone loves astronomy it ain’t a lot worse than in 1980 in the past, most people who stuck it out got good jobs

So what to do? don’t keep on doing your thesis over and over again establish prominent collaborators and mentors, but appear independent publish, publish, publish. Include useful tables of summary and colorful figures that can be easily captured. apply for external funding luck verus hard work become the leader in your field think carefully about joining large projects with time scales of > 5 years. Spergel’s law don’t be afraid to go out on a limb and say something weird. The Aaronson effect in obsevations When you apply for jobs, make sure you know all about the department – and brown nose a bit. Write your application as if there is no other job out there. Know your audience.