Observations, Database, and Pipeline for EoR Jacqueline N. Hewitt MIT Kavli Institute for Astrophysics and Space Research Text

Note: With the descope of LOFAR. MWA-512 is now the most sensitive pathfinder for power spectrum detection Minimum Goal (NSF deliverable!) : subtract foregrounds and have noise-limited EoR limit Goal: detect the power spectrum at some redshift From NSF proposal in 2004

Goal: detect the evolution of the power spectrum with redshift McQuinn et al. (2008), ApJ, 680, 962 Power spectrum slope vs z Power spectrum amplitude vs z

Text Goal: Detect quasar “bubbles” (Attempt is NSF deliverable) Wyithe, Loeb, and Barnes (2006) z=6.5

Text Cross-correlation with galaxy surveys Non-gaussianity of galaxy and star formation Non-gaussianity of some inflation models Separating “gastro-” physics from “real” physics Energy injection via dark matter decay Other Topics of Interest

Text Challenge for all Science Goals: Foreground Subtraction Extensive simulations have been carried out that include Realistic point source population - above and below confusion limit Realistic Galactic emission Realistic primary and synthesized beams (frequency dependence) In these simulations, residual foreground is well below expected EoR signal We have not yet included Antenna calibration errors Polarization Bowman, Morales & Hewitt 2008; Liu, Tegmark & Zaldarriaga 2008; Geil et al. 2008; Jelic et al. 2008; Gleser et al. 2007; Wang et al. 2006; McQuinn et al. 2006; Santos et al. 2005; Di Matteo et al. 2004; Zaldarriaga et al. 2004; Morales & Hewitt 2004; Frulanetto & Briggs 2004; Gnedin & Shaver 2004; Oh & Mack 2003; Di Matteo et al. 2002

Text Purpose of This Session Dipoles Flakey maps Sensitivity calculations Theory Foreground Subtraction sims MAPS & RTS sims of EoR field Bridge the gap!! Get pipeline in place so we can hit the ground running at 512T!! We will present software teams with Grand Challenge simulation

Text David Barnes – data transport, bubble searches Frank Briggs – general builder, data quality, foreground subtraction Judd Bowman – foreground subtraction, power spectrum Chris Carilli - ? Angelica de Oliveira-Costa – foreground modeling Steve Furlanetto – theory, simulations Bryan Gaensler – foreground subtraction Lincoln Greenhill – RTS, bubble searches, survey support Lars Hernquist – theory Jackie Hewitt – data archive, data quality, power spectrum Avi Loeb – theory Colin Lonsdale – general builder Miguel Morales – former RTS, M&C, foreground subtraction, power spectrum Shiv Sethi – drift scan strategies, data quality Max Tegmark – optimum mapping, foreground subtraction, power spectrum Rachel Webster – data archive, bubble searches Stuart Wyithe – foreground subtraction, bubble searches Matias Zaldarriaga - theory Collaboration Members and Their Responsibilities

Text Organized into Sub-work Packages and Coordinators Data Archive – Jackie Hewitt Data Quality – Jackie Hewitt Optimum Mapping – Max Tegmark Foreground Subtraction – Miguel Morales Power Spectrum – Miguel Morales Bubble Searches – Stuart Wyithe Foreground Support – Lincoln Greenhill Theory and Simulation - …….

Text First half of EoR pipeline (work in progress) How to divide time between full sky and EoR field? Is it right not to do the ionospheric correction?

Text Should confusion-level sources be subtracted in uv or image plane? Polarized foregrounds?????????? Verification: what is the appropriate “practice” simulation and Grand Challenge Simulation?

On-Site Storage Monitor and Control RTS Mapper RTS Ionosphere solution Real-Time Computer EoR Real-Time Module On-line quality assessment, editing, and averaging RTS Calibration solution Eor Real- Time Module Supported by MWA Construction Grant

Commissioning - Q1, Q2 and Q Season 1 - Q Q Season 2 - Q Q Target first science results mid- to late-2012 Proposed first public data release (“MWA1”) on 1 Jan 2013 EoR Data Acquisition Assume construction of 512 tiles is complete by early 2010 EoR observing “season” is 1 October - 1 June Two target fields = 1700 hours of observations of EoR fields per season Supported by MWA construction grant

EoR Archives Repository of data at MIT Kavli Institute, with copy at Melbourne U. During commissioning, lots of uv data After commissioning, some uv data for algorithm tests 2-minute integrations of RTS maps Metadata Monitor data base Environment Antenna calibration and ionosphere solutions, point source subtraction record Off-line quality assessment Later, processed data (foregrounds subtracted) Software for access Supported by NSF MRI and $260k MIT contribution

Text 11 September MWA Memo (Morgan & Hewitt) documents database plans 1.1 Maps: 2-minute integrations of I, Q, U, V MWAHealpix maps, FITS header. 50,000 maps per year gives 400 TB 1.2 Metadata Monitor and Control data Commands and instrument response Environmental and system data RTS outputs Calibrator refraction measurements Calibrator gain measurements and peeling record Calibrator Faraday rotation measurements (if done) Primary beam fit parameters Ionospheric rubber sheet fit parameters (if done) Ionospheric Faraday rotation fit parameters 1.3 Data quality: functional derivatives of level 0 data 1.4 Foreground subtracted maps

Text Problem: Calibration solution for one 8-second interval is 164 Mbytes (100 sources X 100 channels X 512 tiles X 4 polprods X 8 bytes) which 1.8 Tbytes/day. Not practical to store this. Possible problem: How much information do we have to store for peeled source list?

Text Technical decisions that need to be made: How to divide observing time between full sky and EoR field? Do we do the ionospheric correction? How do we save the calibration and peeling information? Others will surely arise during this discussion.

Text Collaboration issues: We are developing parallel analyses that have the same goal. Is our publication policy adequate to handle this? (Policy is one must post paper two weeks before submission) Do we need “protection” for student thesis projects? EoR Committee membership no longer represents MWA partners (the partner list has changed). Other issues? We have only 39% of EoR membership here, unfortunately. Need for virtual meeting.