Astroparticle Physics 23 Nathalie PALANQUEDELABROUILLE CEASaclay CERN Summer

Astroparticle Physics (2/3) Nathalie PALANQUE-DELABROUILLE CEA-Saclay CERN Summer Student Lectures, August 2004 1) What is Astroparticle Physics ? Big Bang Nucleosynthesis Cosmic Microwave Background 2) Dark matter, dark energy Evidence for dark matter Candidates and experimental status Supernovae and dark energy 3) High energy astrophysics

Dark matter in clusters Zwicky, 1933 Mass of luminous matter = 10% Gravitational mass Zwicky Amas de Coma 2

Rotation curves (planets) v 2 G m M c m = r r 2 v = Rotation of planets Earth : Saturn : G Mc / r Associated rotation curve 1 yr (at 150 106 km) 30 yrs (at 1, 4 109 km) v=30 km/s v=10 km/s 3

Rotation curve of spiral galaxies NGC 3198 Doppler distortion across galaxy Þ velocity distribution Þ Flat rotation curve ! 90% of gravitational mass is invisible (DARK HALOs) 4

Gravitational lensing Einstein ring HST Luminous mass ~ 1% Gravitational mass 5

Summary of evidence Dark Energy Stars (~2%) (~70%) Non baryonic DM (~25%) Baryonic DM (~3%) W = r / rc W = 1 for k = 0

Lecture outline 1) What is Astroparticle Physics ? Big Bang Nucleosynthesis Cosmic Microwave Background 2) Dark matter, dark energy Evidence for dark matter Candidates and experimental status Baryonic (EROS, MACHO) Exotic (Edelweiss, DAMA, Antares) Supernovae and dark energy 3) High energy astrophysics

Dark matter candidates Baryonic (astrophysical candidates) Non baryonic (particle candidates) Molecular clouds Compact objects s ct je ob du es si re r s as … la m Red dwarfs Neutron stars Black holes el w lo Brown dwarfs White dwarfs st Planets Axions Neutrinos WIMPS

Dark matter candidates Baryonic (astrophysical candidates) Molecular clouds Mi c n e l ro g sin (10 -7 Compact objects Non baryonic (particle candidates) Mass? Neutrinos Msun ~10 Msun) c es s e op n l e t Axions Mass? WIMPS Accelerators Direct search

Principles of microlensing Angular separation of images ~ 10 -3 rad Only 1 (combined) image, amplified Motion of deflector (220 km/s) Duration t. E ~ 90 M/Msun days

Microlensing light curve Luminosity To discriminate against variable stars : Achromatic (Red & Blue) Symmetric Impact parameter 11

Targets (EROS, MACHO) Event rate : ~ 1 per year per 20 million stars monitored Magellanic clouds : 200 000 ly away (edge of halo? ) (Milky Way ~ 70 000 ly in diameter) (not to scale) Milky Way Earth Halo Magellanic Clouds LCM SCM - >10 000 variable stars ~30 million stars monitored: - >100 SN - Microlensing events ? 12

Initial results Candidates (microlensing technique validated), t. E ~ 30 days Over half of the dark halo in the form of dark objects of ~ 0. 5 solar mass ! LCM, 1993 t. E ~ 30 days SMC, 1998 t. E ~ 120 days 13

Final results

White dwarfs White dwarf = final state of low mass star 38 white dwarfs found in old plates - moving fast belongs to halo (vs. disk) - old (i. e. cold) 1 st population of stars in our Galaxy White dwarfs (~1 Msun) may compose 3 to 35% of the halo

Conclusions on baryonic DM Favored candidates (compact astrophysical objects) rejected on all mass range (only small window remaining at ~ 10 -100 Msun) Gas Cold molecular clouds …

Non baryonic DM > 80% of DM is non baryonic Hot DM ? n Cold DM ? Axions WIMPS (invoked to solve strong CP violation pb in SM) Significant if 10 -5 < ma < 10 -3 e. V

Structure formation Simulations of DM density maps Hubble Deep Field HDM wipes out structure on small scales CDM creates too many sub-structures?

Neutrinos as HDM - exist as relic from Big Bang (~ 300 cm-3) - (now) known to have mass: neutrino oscillations 1 10 -1 n masses (e. V) from n oscillations (most likely solution) 10 -2 Atm. n 10 -3 Solar n 10 -4 10 -5 n 1 n 2 n 3 n contribution to matter density: Wv ~ Sm / 46 e. V m ~ 0. 05 e. V Wv ~ 0. 003

Weakly Interacting Massive Particles If SUSY exists - production of sparticles in early universe - all decay except LSP (conservation of R-parity) relic from Big Bang - m ~ 30 Ge. V (accelerator) - annihilate through X X - relic density W ~ 0. 3 for typical weak annihilation rates equilibrium abundance Freeze out actual abundance Increasing <s. Av> Neq e-m /T X = m /T (time )

Direct detection of WIMPS If halo DM made of WIMPS ~ 500 WIMPS/m 3 with v ~ 220 km/s > 10 000 WIMPs/cm 2/s on Earth (from -vsun) Experimental signature : nuclear recoil n WIMP (vs. electronic “recoil”) g e- e- Main source of background (radioactivity) Requirement : High mass detectors Low radioactive background (discrimination)

Background rejection - Deep underground - Event by event discrimination of nuclear vs. electronic recoil ZEPLIN II Diodes HDMS, … Ionisation EDELWEISS, CDMS Scintillators Scintillation Heat CRESST, CUORE, ROSEBUD Bolometers DAMA, ZEPLIN I, UKDMC, … CRESST, ROSEBUD

Annual modulation Motion of Earth in the wind d = 30 o vsun = 220 km/s v. Earth = 30 km/s DAMA Na. I-2 DAMA Na. I-3 Se DA en M by A? DAMA Na. I-1 m ~ 44 -62 Ge. V Modulation of annual rate 7% Max in June DAMA Na. I-4 BUT 1 signature only Not confirmed independantly

Edelweiss: detector In Modane underground laboratory Negligible neutron background (~ 0, 01 evt/kg/day) Dilution cryostat low background (temperature ~15 m. K) Archeological lead shielding Detectors 3 x 320 g bolometers

Edelweiss: analysis 1. 5 Heat + Ionisation Background free analysis No event in signal region Ionisation / recoil Electronic recoil (g) 1 90% 99. 9% Nuclear recoil (WIMP, n) 0. 5 90% 0 0 50 100 150 Recoil energy (ke. V) 200

Conclusions on direct detection Regions above the curves excluded by experiments Regions of WIMPs models

Indirect detection of WIMPs Energy loss by elastic scattering with massive bodies (halos, Earth, Sun, galactic center) Gravitational capture + annihilation Halo gg High energy astronomy AMS, GLAST, VERITAS, BESS, CELESTE, CAPRICE, MILAGRO… Earth, Sun, GC n telescopes Xn Super. K, Baksan, IMB, MACRO AMANDA, ANTARES, Baïkal… Lecture 3

Lecture outline 1) What is Astroparticle Physics ? Big Bang Nucleosynthesis Cosmic Microwave Background 2) Dark matter, dark energy Evidence for dark matter Candidates and experimental status Baryonic (EROS, MACHO) Exotic (Edelweiss, DAMA, Antares) Supernovae and dark energy 3) High energy astrophysics

Geometry of the Universe 1 = Wk(t) + ∑Wx(t) + WL(t) Curvature Energy density of components (matter, radiation) Wg ~ 2. 47 x 10 -5 Density of dark energy Expansion vs geometry: q. O = Wm / 2 - WL

Measurement of the geometry Closed Universe AT A GIVEN DISTANCE Known physical size Known luminosity Flat Universe Open Universe B CM SN Ia angle depends on geometry flux depends on geometry

Life of a small star (<8 Msun)

White dwarfs in binary systems SN Ia Very luminous (L ~ 1010 Lsun), out to high z Standard candles (1. 4 Msun) ~ 1 to 2 / century / galaxy

Light curves Unique parameter (strech factor)

Super. Nova Legacy Survey 3 steps - discovery (differential photometry) 4 deg 2 monitored from CFHT (Hawaii) - identification (spectrum) - photometric follow-up light curve (SNLS : same images as discovery)

CCD detectors at CFHT RCA 1 1981 -1986 1 CCD, 320 x 512 champ 2’ x 3. 5’ RCA 2 1986 -1995 1 CCD, 640 x 1024 champ 2’ x 3. 5’ SAIC 1 1990 1 CCD, 1 K x 1 K champ 4. 2’ x 4. 2’ Lick 2 1992 1 CCD, 2 K x 2 K champ 7’ x 7’ UH 8 K 1996 8 CCDs, 8 K x 8 K champ 28’ x 28’ CFH 12 K 1999 12 CCDs, 12 K x 8 K champ 42’ x 28’ Mega. Cam 2002 40 CCDs, 20 K x 18 K champ 1° x 1° MOCAM 1994 4 CCDs, 4 K x 4 K champ 14’ x 14’

Hubble diagram m = - 2. 5 log F + cst = 5 log (H 0 DL) + M - 5 log H 0 + 25 fainter cz 0 Magnitude m H 0 D L z mesure de H 0 z grand : mesure de Wm, WL Accelerated expansion = smaller rate in the past WL = more time to reach a given z = larger distance of propagation of the photons = smaller flux Supernova Cosmology Project 1+z = a(tobs)/a(tem) At a given z Calan Tololo Hamuy et al. , A. J. 1996 Redshift z older

Initial constraints (1998) 42 supernovae q 0 = WM/2 - WL < 0 : Accelerating Universe If flat (Wtot = 1) : WM = 0. 28 WL = 0. 72

Concordance 2000 2002 LSS CMB Expected precision with JDEM (>2010)