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Planck 2015 Data Release

  1. Feb 4, 2015 #1
    The Planck 2015 (formerly 2014) Data Release will finally be released to the public tomorrow February 5. Details at-

    http://www.cosmos.esa.int/web/planck
     
  2. jcsd
  3. Feb 4, 2015 #2

    Borg

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    Nice. Now if I only had the time to look at it all.
     
  4. Feb 4, 2015 #3

    Garth

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    Thank you websterling for that heads-up!

    I wonder whether Planck 2015 will shed any light on the gravity wave/dust controversy?

    We wait and see.....

    Garth
     
  5. Feb 4, 2015 #4

    marcus

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    This came out yesterday, caveat lector. Roughly 270 authors are listed (216 plus something over 50).
    http://arxiv.org/abs/1502.00612
    A Joint Analysis of BICEP2/Keck Array and Planck Data
    BICEP2/Keck, Planck Collaborations: P. A. R. Ade, N. Aghanim, Z. Ahmed, R. W. Aikin, K. D. Alexander, M. Arnaud, J. Aumont, C. Baccigalupi, A. J. Banday, D. Barkats, R. B. Barreiro, J. G. Bartlett, N. Bartolo, E. Battaner, K. Benabed, A. Benoit-Lévy, S. J. Benton, J.-P. Bernard, M. Bersanelli, P. Bielewicz, C. A. Bischoff, J. J. Bock, A. Bonaldi, L. Bonavera, J. R. Bond, J. Borrill, F. R. Bouchet, F. Boulanger, J. A. Brevik, M. Bucher, I. Buder, E. Bullock, C. Burigana, R. C. Butler, V. Buza, E. Calabrese, J.-F. Cardoso, A. Catalano, A. Challinor, R.-R. Chary, H. C. Chiang, P. R. Christensen, L. P. L. Colombo, C. Combet, J. Connors, F. Couchot, A. Coulais, B. P. Crill, A. Curto, F. Cuttaia, L. Danese, R. D. Davies, R. J. Davis, P. de Bernardis, A. de Rosa, G. de Zotti, J. Delabrouille, et al. (216 additional authors not shown)
    (Submitted on 2 Feb 2015)
    We report the results of a joint analysis of data from BICEP2/Keck Array and Planck. BICEP2 and Keck Array have observed the same approximately 400 deg2 patch of sky centered on RA 0h, Dec. −57.5deg. The combined maps reach a depth of 57 nK deg in Stokes Qand U in a band centered at 150 GHz. Planck has observed the full sky in polarization at seven frequencies from 30 to 353 GHz, but much less deeply in any given region (1.2 μK deg in Q and U at 143 GHz). We detect 150×353 cross-correlation in B-modes at high significance. We fit the single- and cross-frequency power spectra at frequencies above 150 GHz to a lensed-ΛCDM model that includes dust and a possible contribution from inflationary gravitational waves (as parameterized by the tensor-to-scalar ratio r). We probe various model variations and extensions, including adding a synchrotron component in combination with lower frequency data, and find that these make little difference to the r constraint. Finally we present an alternative analysis which is similar to a map-based cleaning of the dust contribution, and show that this gives similar constraints. The final result is expressed as a likelihood curve for r, and yields an upper limit r0.05<0.12 at 95% confidence. Marginalizing over dust and r, lensing B-modes are detected at 7.0σsignificance.
    Comments: Provisionally accepted by PRL. Data and figures available for download at this http URL and this http URL

    My comment: they got a lot of people on board.
     
  6. Feb 4, 2015 #5
    The Planck site has a nice article about this-

    http://www.esa.int/Our_Activities/Space_Science/Planck/Planck_gravitational_waves_remain_elusive

    Contrary to what others are reporting, their consensus is that it's mostly dust and microlensing, and that it sets an upper limit on the amount of gravitational waves from inflation- probably no more than about half the observed signal.

    It does not, as has been claimed, mean that inflation, gravity waves from inflation, B-mode polarization of the CMB from gravity waves from inflation, or anything else is dead.

    Résonaances has just posted his perspective-

    http://www.resonaances.blogspot.it/2015/02/b-modes-whats-next.html
     
    Last edited: Feb 4, 2015
  7. Feb 4, 2015 #6

    Chalnoth

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    My take-away:
    No evidence of primordial B-modes, but they did see the lensed B-modes very clearly (gravitational lensing of large scale structure in the universe mixes E-mode polarization into B-modes).
     
  8. Feb 4, 2015 #7

    marcus

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    Résonaances has a great Monty Python clip about the Taunting Frenchman! Thoughtful comment on the whole affair. The question that Paul Steinhardt raises (including at the Paris December 2014 Planck results conference) is not about inflation being dead, but that it is not science because it accommodates to any and all findings (BICEP or not BICEP, high r or low) with a cheerful cry of "I told you so!

    Not dead in other words, just altogether too flexible.
     
  9. Feb 4, 2015 #8

    Chalnoth

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    That's a really terrible critique. Inflation makes more than just one prediction, and some of those predictions has been borne out by observation.

    With regard to the B-mode signal, for example, there is a relationship between the power spectra between the B-mode, E-mode, and temperature signals. A detection of the B-mode signal should also produce a signal in the others. Furthermore, narrowing the parameter space available for inflation is the very essence of doing science. The fact that the total parameter space incorporates a wide variety of possible observations is irrelevant: the observations do say something definitive about the nature of inflation.
     
  10. Feb 4, 2015 #9

    marcus

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    And the predictions which it makes are also made by OTHER frameworks which do NOT have the excessive flexibility problem Steinhardt refers to :)
    But I would have no interest in arguing with a true believer, whose faith in the inflation paradigm nothing can shake, so I hope you are not such.
    Actually come to think of it, I don't much fancy arguing about this at all.:)
    I might just give some Steinhardt links and leave it at that. Here is his June 2014 Nature article
    Big Bang Blunder Bursts the Multiverse Bubble
    http://www.nature.com/news/big-bang-blunder-bursts-the-multiverse-bubble-1.15346
     
  11. Feb 4, 2015 #10

    cristo

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    Let's try and keep this thread on topic, regarding the forthcoming Planck data release due tomorrow afternoon, and not about alternatives to inflation.
     
  12. Feb 4, 2015 #11

    marcus

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    Definitely, cristo! One simply has to recognize that the alternatives exist. that the inflation picture is not the "only game in town". It is not something that needs to be discussed.
    I agree very much to keep thread focussed on forthcoming release of Planck data. (in fact some seems to have been released already see posts #3 and #4)
     
    Last edited: Feb 4, 2015
  13. Feb 5, 2015 #12
  14. Feb 5, 2015 #13

    marcus

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    Impressive it sure is! A really fine accomplishment. Of particular interest to us in Cosmo forum is the "Cosmological Parameters" paper:
    http://www.cosmos.esa.int/documents...015_Results_XIII_Cosmological_Parameters.pdf/
    and the highlights (including the point about the inflation-relevant tensor-scalar ratio "r" you mentioned, but much else besides) is up front in the summary. People may be interested in glancing at a few highlights of the abstract:
    ==quote==
    Planck 2015 results. XIII. Cosmological parameters
    February 5 2015

    ABSTRACT
    This paper presents cosmological results based on full-mission Planck observations of temperature and polarization anisotropies of the cosmic microwave background (CMB) radiation. Our results are in very good agreement with the 2013 analysis of the Planck nominal-mission temperature
    data, but with increased precision. The temperature and polarization power spectra are consistent with the standard spatially-flat six-parameter ΛCDM cosmology with a power-law spectrum of adiabatic scalar perturbations (denoted “base ΛCDM” in this paper). From the Planck temperature data combined with Planck lensing, for this cosmology we find a Hubble constant, H0 = (67.8 ± 0.9) km s−1 Mpc−1 , a matter density parameter Ωm = 0.308 ± 0.012, and a tilted scalar spectral index with ns = 0.968 ± 0.006, consistent with the 2013 analysis. (In this abstract we quote 68 % confidence limits on measured parameters and 95 % upper limits on other parameters.) We present the first results of polarization measurements with the Low Frequency Instrument at large angular scales. Combined with the Planck temperature and lensing data, these measurements give a reionization optical depth of τ = 0.066 ± 0.016, corresponding to a reionization redshift of zre = 8.8−1.4+1.7.. These results are consistent with those from WMAP polarization measurements cleaned for dust emission using 353 GHz polarization maps from the High Frequency Instrument. We find no evidence for any departure from base ΛCDM in the neutrino sector of the theory. For example, combining Planck observations with other astrophysical data we find Neff = 3.15±0.23 for the effective number of relativistic degrees of freedom, consistent with the value Neff = 3.046 of the Standard Model of particle physics. The sum of neutrino masses is constrained to ∑mν < 0.23 eV. The spatial curvature of our Universe is found to be very close to zero with |ΩK| < 0.005. Adding a tensor component as a single-parameter extension to base ΛCDM we find an upper limit on the tensor-to-scalar ratio of r0.002 < 0.11, consistent with the Planck 2013 results and consistent with the B-mode polarization constraints from a joint analysis of BICEP2, Keck Array, and Planck (BKP) data. Adding the BKP B-mode data to our analysis leads to a tighter constraint of r0.002 < 0.09 and disfavours inflationary models with a V(φ) ∝ φ2 potential. The addition of Planck polarization data leads to strong constraints on deviations from a purely adiabatic spectrum of fluctuations. We find no evidence for any contribution from isocurvature perturbations or from cosmic defects. Combining Planck data with other astrophysical data, including Type Ia supernovae, the equation of state of dark energy is constrained to w = −1.006 ± 0.045, consistent with the expected value for a cosmological constant. The standard big bang nucleosynthesis predictions for the helium and deuterium abundances for the best-fit Planck base ΛCDM cosmology are in excellent agreement with observations. We also analyse constraints on annihilating dark matter and on possible deviations from the standard recombination history. In both cases, we find no evidence for new physics. The Planck results for base ΛCDM are in good agreement with baryon acoustic oscillation data and with the JLA sample of Type Ia supernovae. However, as in the 2013 analysis, the amplitude of the fluctuation spectrum is found to be higher than inferred from some analyses of rich cluster counts and weak gravitational lensing. We show that these tensions cannot easily be resolved with simple modifications of the base ΛCDM cosmology. Apart from these tensions, the base ΛCDM cosmology provides an excellent description of the Planck CMB observations and many other astrophysical data sets.
    ==endquote==
    A minor point, but it looks like the parameters in Jorrie's "Lightcone" calculator, which we've been using quite a bit in Cosmo forum, are still good. They correspond to null spatial curvature, which keeps getting confirmed, and the now and future Hubble radiuses 14.4 and 17.3 Gly which give H0 and matter fraction values of 67.9 km/s per Mpc and 0.307.
     
    Last edited: Feb 5, 2015
  15. Feb 6, 2015 #14
    this is nice
     
  16. Feb 6, 2015 #15

    jim mcnamara

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    Confusion on my part:
    http://www.esa.int/Our_Activities/Space_Science/Planck/Planck_reveals_first_stars_were_born_late

    This claims the Planck data show that the first stars came to be ~100 million years later than previous estimates. Or the 'Dark Ages' of the early universe ended later than previously thought.

    This is not my field. I have a persistent credibility problem instantiated with earlier BICEP2 interpretations, plus, I have no way to judge:
    Is this a solid, reasonable position to take, or do I take it as merely a hopefully slightly better gross estimate than the previously given value?

    Thanks for opinions!
     
  17. Feb 6, 2015 #16
    Current status of the Planck 2015 Results-

    The release consists of 28 papers of which 18 are online and have been submitted to Astronomy & Astrophysics, 8 are listed as "in prep", and 2 (including the Inflation paper) are listed as "to be submitted in the next days"

    The main Planck page also has the notice "Additional 2015 products will be released near the end of March 2015"

    Also most of the data is available in the Planck Legacy Archive.
     
  18. Feb 7, 2015 #17
    I just saw this Planck view of the milky way and wanted to ask, if all the galaxies in the U are radiating this much diffuse microwave energy, then how much might this total galaxy microwave output for the whole universe, along with the wide spread of red shifts, contribute to the amplitude of the cmbr measurements? My apologies If this is in the wrong place, I will gladly delete and start a new thread.

    http://www.space.com/28478-spectacular-milky-way-maps-planck-images.html
     
    Last edited: Feb 7, 2015
  19. Feb 7, 2015 #18

    Chalnoth

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    1. At the frequencies where the CMB is brightest, the small deviations in temperature are *much* brighter than the light from our own galaxy, except very close to the galactic center. Other galaxies further away are all much dimmer than the CMB at these frequencies.
    2. The way the brightness of galaxies changes with frequency is extremely different from the way the CMB changes with frequency. So when you measure the sky at many frequencies (9 in Planck's case), it's relatively easy to distinguish between light coming from the CMB and light coming from other sources.
     
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