Observational Cosmology

Observational Cosmology

Observational cosmology R. A. Burenin IKI, Moscow Baikal School 2014 Cosmic microwave background T = 2.725 К CMB anisotropy − δT/T ∼ 10 5 Planck collaboration, 2013 RELIKT-1 experiment RELIKT-1 at PROGNOZ-9 IKI, USSR, 1983–1984 RELIKT-2 at IKI: CMB anisotropy RELIKT-1 (IKI) 37 GHz CMB map ◦ 5.5 resolution Strukov et al., AstL, 1992 CMB anisotropy Hot spots are there! Planck collaboration, 2013 CMB anisotropy RELIKT-1 cold spot — questioned by COBE, but confirmed with WMAP Sculachev, UFN, 2010 Cosmic Background Explorer (COBE) NASA, 1989–1992 CMB anisotropy 7◦ res. COBE 30–90 GHz CMB map, 1992 Nobel Prize, 2006 CMB anisotropy Planck collaboration, 2013 Balloon experiments BOOMERanG: 1998, Caltech + La Sapienza 42 km alt., 2 weeks flight, 1.2-m, <1◦ ang. res., bolometers + MAXIMA and others CMB anisotropy power spectrum BOOMERanG + MAXIMA: e.g., Ωtot = 1.11 ± 0.07 Jaffe et al., 2001 CMB anisotropy power spectrum The end of 2001: Hu, Dodelson, ARA&A, 2002 Wilkinson Microwave Anisotropy Probe (WMAP) NASA, 2001–2009 CMB anisotropy WMAP, 2003–2011 CMB anisotropy Planck collaboration, 2013 CMB anisotropy power spectrum e.g., Ωk = −0.015 ± 0.020 3-year WMAP data, Spergel et al., 2006 CMB anisotropy power spectrum 7-year WMAP data, Larson et al., 2011 Limited by cosmic variance at l< 550 Athmospheric Transparancy in Microwave — CMB may be observed in Rayleigh–Jeans part of the spectrum from Earth surface — better to do it in a dry place Atacama Cosmology Telescope 5190 m alt., 6-m mirror, 1′ res. South Pole Telescope 10-m, 1′ res. CMB anisotropy power spectrum WMAP, SPT, ACT, Hinshaw et al., 2013 Planck LFI: 30, 44, 70 GHz; HFI: 100, 143, 217, 353, 545, 857 GHz 25 times more sensitive, 3 times better angular resolution (5′), as compared to WMAP ESA, 2009–2013, main phase – 12 month, total HFI — 29 month, Dec. 2014 — final data release CMB + foregrounds Planck collaboration, 2013 CMB anisotropy Planck collaboration, 2013 Component separation power specrtum of CMB + foregrounds: Planck collaboration, 2013 CMB anisotropy power spectrum cosmic variance limited at l < 1500 Planck collaboration, 2013 CMB anisotropy power spectrum 2 2 Ωtot =1, ΩΛ =0.65, Ωbh =0.020, Ωmh =0.147, n =1 Hu, Dodelson, ARA&A, 2002 Secondary CMB anisotropies + • Reionization • Gravitational lensing • Sunyaev-Zeldovich effect • . Planck 2013 results ΛCDM as compared to WMAP: “concordant” → “discordant” cosmology Planck 2013 results Tension in Ωm as compared to supernovae (disappeared). Planck 2013 results Tension in H0 as compared to local measurements. Planck 2013 results Tension in σ8 as compared to local measurements. Planck 2013 results CMB polarization Hu, Dodelson, ARA&A, 2002 BICEP-2 experiment BICEP-2 experiment — refractor telescope — 512 pol. sensitive TES bolometers at 250 mK BICEP-2 results BICEP2 collaboration, 2014 (20 June) BICEP-2 results BICEP2 collaboration, 2014 (20 June) Comments on BICEP-2 results • Dust polarization signal? — Flauger et al., arXiv:1405.7351 • Planck data? — “. Planck’s sensitivity allows in principle to measure the tensor-to-scalar ratio at the high level of signal detected by BICEP2, though in practice this depends on controlling systematic effects and foregrounds. ” — we should wait until Dec. 2014 Ongoing CMB experiments • SPTpol — observing since 2012, B-modes from lensing: arXiv:1307.5830 • ACTPol — observing since 2013, first results on E-modes: arXiv:1405.5524 • Keck Array at South Pole (2011–2014) • BICEP3 planned to start oberving in 2015 Future CMB experiments from the talk by J. Delabrouille (COrE+) at Zeldovich-100 conference, June 2014, Moscow Cosmological parameters constraints Komatsu et al., 2009 Cosmological parameters constraints Planck + BAO: Planck collaboration, 2013 The other cosmological data are also important. Baryon acoustic oscillations Martinez, 2009 (from Gorbunov, Rubakov, 2010) Sloan Digital Sky Survey (SDSS) 2.5-m pri. (1-m sec.), 3◦ diameter FOV SDSS imaging camera SDSS sky coverage imaging: 15000 sq. deg. — almost all Northern extragalactic sky SDSS spectrograph SDSS spectrograph SDSS spectrograph SDSS sky coverage spectroscopy: 1,848,851 galaxy spectra, 308,377 quasar spectra Luminous red galaxies (LRG) redshift survey Baryon Oscillation Spectroscopic Survey (BOSS) LRG power spectrum SDSS, BOSS, Anderson et al., 2012 LRG power spectrum SDSS, BOSS, Anderson et al., 2014 LRG power spectrum SDSS, BOSS, Anderson et al., 2014 Lyα forest Varshalovitch et al., AstL, 2001 BAO in Lyα forest 90 80 70 H(z)/(1+z) (km/sec/Mpc) 60 50 0 1 2 z Delubac et al., AstL, 2014; Busca et al., 2013 Future BAO measurements eBOSS, 2014–2020: Future BAO measurements Javalambre Physics of Accelerated Universe Survey (J-PAS) Future BAO measurements Javalambre Physics of Accelerated Universe Survey (J-PAS) telescope — 2.5-m M1 FOV — 3◦ diameter grasp = 27.5 m2 deg2, LRG redhifts up to z ≈ 1 + more science Telescopes with wide FOV 1-m Schmidt, Burakan, Armenia 1.6-m, 3◦ diameter FOV telescope max. grasp: ≈20 m2 deg2 at Sayan Observatory real: ≈7 m2 deg2 max. grasp: 14.2 m2 deg2 Supernovae type Ia a¨ > 0 — e.g., Riess et al., 1998 (Nobel Prize 2011): Supernovae type Ia More recent data: UNION2, Amanullah et al., 2010 — Dominated by systematic uncertainties. Absolute magnitudes of supernovae type Ia HST, NGC5584: Absolute magnitudes of supernovae type Ia Absolute magnitudes of supernovae type Ia Hubble constant SNe Ia at z < 0.1 with calibrated absolute magnitudes. −1 −1 H0 = 73.8 ± 2.4 km s Mpc Riess et al., 2011 Large scale structure of the Universe Millenium simulations z = 18.3, 5.7, 1.4, 0 (t = 0.21, 1, 4.7, 13.6 Gyear) Matter power spectrum from LRG redshift survey but σ8 is not constrained Reid et al., 2009 The dark matter – galaxy bias Weak gravitational lensing, cosmic shear A1689 CFHT MegaCam 3.6-m telescope, Mauna Kea, Hawaii 1 sq. deg. FOV 36 2048 x 4612 pixel CCDs CFHTLens 154 sq.deg., 0.8′′, ugriz: Kilbinger et al., 2013 Future gravitational lensing measurements Dark Energy Survey, 5000 sq.deg. Future gravitational lensing measurements 8-m Subaru telescope, Hyper Suprime-Cam (HSC)— 1.5◦ diameter FOV Future gravitational lensing measurements Large Synoptic Survey Telescope (LSST) 8.4-m telescope, 9.6 sq. deg. FOV, <0.7′′ seeing, 2023 — ... Future gravitational lensing measurements Euclid 1.2-m space telescope, 15000 sq. deg. survey, 2020 — 2026 Large scale structure — density perturbations growth can be measured using galaxy clusters The number of collapsed objects 3 ′ ′ ′ δR(x) ≡ d x δ(x )WR(x − x ) Z The number of collapsed objects 2 2 σR ≡ hδR(x)i, σM = σR(R(M)) −1 dn ρm d ln σ = f(σ) dM M dM ≈5% accuracy Tinker, Kravtsov, Klypin et al., 2008 Dependence on cosmological parameters + σ8 from the MF normalization What we need to measure cluster mass function? We need: • to detect clusters in a well defined survey • to measure their masses Coma cluster Projection effects — projection effects hamper cluster detection in optical X-ray emission of hot intracluster gas T ∼ 3–10 keV, ≈ 90% baryon mass Galaxy cluster 1E 0657-558 (Bullet cluster) — dark matter do exist! ROSAT — «roentgen satellite» grazing incidence reflection optics, Wolter type telescopes: Germany (+USA and GB), 1990–1999 Chandra observatory NASA, 1999 – . XMM-Newton observatory ESA, 1999 – ... Galaxy clusters in ROSAT images Cluster detection procedure 160d, Vikhlinin et al., 1998, ApJ, 502, 558 image → wavelet-decomposition → maximum likelihood fitting + Monte-Carlo simulations Optical observations Russian-Turkish 1.5-m Telescope (RTT150) Russian-Turkish 1.5-m Telescope (RTT150) • Produced at LOMO, St.-Petersburg, Russia • Installed at Bakyrlytepe, Turkey, first light in 2000 • Operated by KFU, IKI and TUG Russian-Turkish 1.5-m Telescope (RTT150) TFOSC — TUBITAK Faint Object Spectrograph and Camera similar to, e.g., ALFOSC at NOT and others 6-m telescope of SAO RAN Bolyshoy Telescop Azimutalyny, BTA 6-m telescope of SAO RAN Bolyshoy Telescop Azimutalyny, BTA 6-m telescope of SAO RAN SCORPIO spectrograph and camera: Afanasiev & Moiseev, 2005 AZT-33IK 1.6-m telescope of Sayan Observatory Sectrograph is now produced at SAO RAN (ordered by IKI RAN). Direct images PSZ1 G098.24-41.15, z = 0.4362 Direct images PSZ1 G100.18-29.68, z = 0.485 Direct images PSZ1 G138.11+42.03, z =0.496 Direct images PSZ1 G209.80+10.23, z =0.677 Photometric redshifts δz/(1 + z) ≈ 0.03, calibrated using 400d survey data (Burenin et al., 2007) Redshift measurements MgI NaD Keck II, Magellan, ESO 3.6-m, NTT, FLWO 1.5-m, NOT, Danish 1.54-m + BTA and RTT150 400d galaxy cluster survey Luminosity function: Burenin, Vikhlinin, Hornstrup et al., 2007 How do we measure cluster masses? Kravtsov, Vikhlinin, Nagai, 2006 Weak gravitational lensing A1689 Mass scale calibration δM/M ≈ 0.09 Chandra Cluster Cosmology Project — CCCP z < 0.1 z > 0.45 86 nearby (RASS) and distant (400d) clusters Galaxy cluster mass function Vikhlinin et al., 2009, ApJ, 672, 1060 Galaxy cluster mass function New independent confirmation of the existance of dark energy. Vikhlinin et al., 2009, ApJ, 672, 1060 Dark eneregy constraints Vikhlinin et al., 2009, ApJ, 672, 1060 Dark eneregy constraints Vikhlinin et al., 2009, ApJ, 672, 1060 Markov Chain Monte-Carlo (MCMC) e.g. Lewis & Bridle, 2002 Metropolis-Hastings algorythm. The every next point accepted with probability: P (θn+1)q(θn+1, θn) α(θn, θn+1) = min 1, P (θn)q(θn, θn+1) where q(θn, θn+1) — arbitrary proposal distribution. It can be shown that P (θ) — equilibrium distribution of the chain. The amount of calculations needed to explore P (θ) is approximately proportional to the number of parameters, not as a power of this number as for the calculations on a grid.

View Full Text

Details

  • File Type
    pdf
  • Upload Time
    -
  • Content Languages
    English
  • Upload User
    Anonymous/Not logged-in
  • File Pages
    139 Page
  • File Size
    -

Download

Channel Download Status
Express Download Enable

Copyright

We respect the copyrights and intellectual property rights of all users. All uploaded documents are either original works of the uploader or authorized works of the rightful owners.

  • Not to be reproduced or distributed without explicit permission.
  • Not used for commercial purposes outside of approved use cases.
  • Not used to infringe on the rights of the original creators.
  • If you believe any content infringes your copyright, please contact us immediately.

Support

For help with questions, suggestions, or problems, please contact us