The astro -ph “Reader’s Digest”

1. Astrobites The astro-ph “Reader’s Digest” astrobites.org Christopher M. Faesi (Harvard Univ.) on behalf of the Astrobites collaboration AAS 222nd Meeting Indianapolis, IN June 4, 2013

2. 222nd AAS Meeting Nine-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Cosmological Parameter Results G. Hinshaw and the WMAP Team We present cosmological parameter constraints based on the final nine-year WMAP data, in conjunction with additional cosmological data sets. The WMAP data alone, and in combination, continue to be remarkably well fit by a six-parameter LCDM model. When WMAP data are combined with measurements of the high-l CMB anisotropy, the BAO scale, and the Hubble constant, the densities, Omegabh2, Omegach2, and Omega_L, are each determined to a precision of ~1.5%. The amplitude of the primordial spectrum is measured to within 3%, and there is now evidence for a tilt in the primordial spectrum at the 5sigma level, confirming the first detection of tilt based on the five-year WMAP data. At the end of the WMAP mission, the nine-year data decrease the allowable volume of the six-dimensional LCDM parameter space by a factor of 68,000 relative to pre-WMAP measurements. We investigate a number of data combinations and show that their LCDM parameter fits are consistent. New limits on deviations from the six-parameter model are presented, for example: the fractional contribution of tensor modes is limited to r<0.13 (95% CL); the spatial curvature parameter is limited to -0.0027 (+0.0039/-0.0038); the summed mass of neutrinos is <0.44 eV (95% CL); and the number of relativistic species is found to be 3.84+/-0.40 when the full data are analyzed. The joint constraint on Neff and the primordial helium abundance agrees with the prediction of standard Big Bang nucleosynthesis. We compare recent PLANCK measurements of the Sunyaev-Zel'dovich effect with our seven-year measurements, and show their mutual agreement. Our analysis of the polarization pattern around temperature extrema is updated. This confirms a fundamental prediction of the standard cosmological model and provides a striking illustration of acoustic oscillations and adiabatic initial conditions in the early universe. http://arxiv.org/abs/1212.5226

3. 222nd AAS Meeting Jargon Alert! Nine-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Cosmological Parameter Results G. Hinshaw and the WMAP Team We present cosmological parameter constraints based on the final nine-year WMAP data, in conjunction with additional cosmological data sets. The WMAP data alone, and in combination, continue to be remarkably well fit by a six-parameter LCDM model. When WMAP data are combined with measurements of the high-l CMB anisotropy, the BAO scale, and the Hubble constant, the densities, Omegabh2, Omegach2, and Omega_L, are each determined to a precision of ~1.5%. The amplitude of the primordial spectrum is measured to within 3%, and there is now evidence for a tilt in the primordial spectrum at the 5sigma level, confirming the first detection of tilt based on the five-year WMAP data. At the end of the WMAP mission, the nine-year data decrease the allowable volume of the six-dimensional LCDM parameter space by a factor of 68,000 relative to pre-WMAP measurements. We investigate a number of data combinations and show that their LCDM parameter fits are consistent. New limits on deviations from the six-parameter model are presented, for example: the fractional contribution of tensor modes is limited to r<0.13 (95% CL); the spatial curvature parameter is limited to -0.0027 (+0.0039/-0.0038); the summed mass of neutrinos is <0.44 eV (95% CL); and the number of relativistic species is found to be 3.84+/-0.40 when the full data are analyzed. The joint constraint on Neff and the primordial helium abundance agrees with the prediction of standard Big Bang nucleosynthesis. We compare recent PLANCK measurements of the Sunyaev-Zel'dovich effect with our seven-year measurements, and show their mutual agreement. Our analysis of the polarization pattern around temperature extremais updated. This confirms a fundamental prediction of the standard cosmological model and provides a striking illustration of acoustic oscillations and adiabatic initial conditions in the early universe. http://arxiv.org/abs/1212.5226

4. 222nd AAS Meeting Astrobites to the rescue! Understandable title Category links Direct link to astro-ph article Accessible language

5. 222nd AAS Meeting Origins and Mission Founded: November 2010 by Nathan Sanders and four other Harvard astronomy graduate students The Astrobites Mission: • Inform our readers by summarizing recent astronomy results • Educate students and the public on research methods, terminology, and technical background • Inspire the next generation of scientists

6. 222nd AAS Meeting Who reads Astrobites? Astrobites reaches more than 500 readers per day astrobites.org: unique visitors by month: June 2012-May 2013 • Target audience: Undergraduates with minimal physics background • Actual audience: • Students (Grad + Undergrad) • Professional astronomers • Astronomy enthusiasts • Educators Note: 2/3 of our readers access astrobites through email or RSS feeds From Google analytics US Readers by location Data from Oct./Nov. 2012 survey

7. 222nd AAS Meeting Who writes for Astrobites? • 26 Graduate student authors from 17 institutions worldwide • Authors post and edit once each per month • > 700 articles published to date • 100% student-run Astrobites Author Institutions

8. 222nd AAS Meeting Beyond the Blog • Astrobites as a classroom resource (N.E. Sanders et al. 2012, Astronomy Education Review, 11 (1), 010201) • Communicating Science 2013: A workshop for Graduate students (workshop.astrobites.com) • Model for other science ‘bites websites: e.g. chembites.org

9. 222nd AAS Meeting Thanks! astrobites.org Nick Ballering (U. AZ) Aaron Bray (Harvard) Elisa Chisari (Princeton) Ian Czekala (Harvard) Jessica Donaldson (U. MD) Courtney Dressing (Harvard) Maria Drout (Harvard) Chris Faesi (Harvard) Ryan Foltz (UC Riverside) Josh Fuchs (UNC Chapel Hill) Dan Gifford (U. MI) Nathan Goldbaum (UCSC) Shannon Hall (U. WY) Nick Hand (UC Berkeley) KiritKarkare (Harvard) Michelle Kislak (UCLA) Susanna Kohler (U. CO Boulder) TanmoyLaskar (Harvard) Elizabeth Lovegrove (UCSC) Betsy Mills (UCLA) Ben Montet (Caltech) Kevin Moore (UC Santa Barbara) Lucia Morganti (MPE Garching) Caroline Morley (UCSC) Erika Nesvold (U. MD) Elisabeth Newton (Harvard) Joe O’Rourke (Caltech) Alice Olmstead (U. MD) Tony Pan (Harvard) Kim Phifer (UCLA) Adele Plunkett (Yale/U. Chile) SukritRanjan (Harvard) Anna Rosen (UCSC) Katherine Rosenfeld (Harvard) Nathan Sanders (Harvard) Evan Schneider (U. AZ) Zack Slepian (Harvard) Allison Strom (Caltech) Josh Suresh (Harvard) Justin Vasel (U. MN Duluth) Lauren Weiss (UC Berkeley)