Photometric Redshift Cosmic Surveys: ALHAMBRA and J-PAS. Alberto Fernández Soto Instituto de Física de Cantabria (CSIC-UC)

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1 Photometric Redshift Cosmic Surveys: ALHAMBRA and J-PAS Alberto Fernández Soto Instituto de Física de Cantabria (CSIC-UC) viernes 14 de diciembre de 2012

2 Abstract The need for cosmic surveys Spectroscopy and photometry Photometric redshifts at work ALHAMBRA: Cosmic evolution J-PAS: Dark energy and galaxy formation viernes 14 de diciembre de 2012

3 A fraction of the Sky - 4x3 arcminutes - Hundreds of objects - All of them (...) galaxies viernes 14 de diciembre de 2012

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5 How Do we Measure Galaxy Redshifts? Spectroscopy: Accurate and Expensive Photometry: Approximate and Cheap viernes 14 de diciembre de 2012

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9 z = z = Spectroscopy z = REDSHIFT MACHINES z = One slit or fiber per object z = Light goes through grating Collection on CCD z = z = Electronic acquisition and processing Final spectrum for line ID ing z = z = z = viernes 14 de diciembre de 2012

10 State-of-the-art Spectroscopy The (relatively near future) new generation of masive spectrographs will be able to obtain spectra for ~1000 objects at once 8m telescope ==> <1 degree field 4m telescope ==> ~1 degree field 2m telescope ==> No cosmology viernes 14 de diciembre de 2012

11 An Alternative We could use the general shape of the spectrum (instead of the position of narrow features) to decide the redshift of a galaxy This general shape can be revealed by photometry alone viernes 14 de diciembre de 2012

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23 State-of-the-art Imaging New generation of dedicated telescopes equipped with massive cameras (>1 Gpix), able to image from the UV cut to the IR end 8m telescope ==> No sizable field 4m telescope ==> ~1 sqdegree field 2m telescope ==> ~5 sqdegree field viernes 14 de diciembre de 2012

24 To Infinity and Beyond? What is a good strategy to choose? Why are we performing large photometric cosmic surveys? viernes 14 de diciembre de 2012

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34 Photometric Redshifts Photometric redshift techniques offer Accuracy ~7% for standard photometry Accuracy ~2% for 20-band photometry Accuracy ~.3% for 50-band photometry Compare to perfect values in spectroscopy Photo-z preferred in large tasks SURVEYS viernes 14 de diciembre de 2012

35 ALHAMBRA Advanced Large Homogeneous Area Medium Band Redshift Astronomical Survey viernes 14 de diciembre de 2012

36 ...in a nutshell TARGET: Cosmic Evolution MEANS: 600,000 galaxies with photo-z DATA: 20 optical + 3 NIR bands INSTRUMENT: 3.5m Calar Alto (Almería) DATES: Database becomes public Dec 12 viernes 14 de diciembre de 2012

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38 Reach of ALHAMBRA Images: AB[ Å] ~ 25 Area: 4 sqdeg in eight fields Objects: Spectra: AB ~ 23 Accuracy: Δz/(1+z) 0.03 Depth: <z> ~ 0.75 viernes 14 de diciembre de 2012

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42 Matute et al. 2012, 2013 Photometric selection of QSOs in ALHAMBRA fields GTC-Osiris Spectrum z=5.5 viernes 14 de diciembre de 2012

43 Bongiovanni et al Lyman α emitters in ALHAMBRA and Herschel data

44 Stefanon 2011 (PhD Thesis, UV) Segregated ALHAMBRA Luminosity Functions to z=1.25

45 Arnalte-Mur 2011 (PhD Thesis, UV) Galaxy Clustering to z=1.25 in ALHAMBRA

46 Galaxy Morphology and Mergers in ALHAMBRA fields viernes 14 de diciembre de 2012

47 Galaxy Clusters and Groups in ALHAMBRA fields viernes 14 de diciembre de 2012

48 J-PAS Javalambre - Physics of the Accelerating Universe Astronomical Survey viernes 14 de diciembre de 2012

49 ...in a nutshell TARGET: Dark Energy parameters (BAOs) MEANS: 100,000,000 LRGs with photo-z DATA: 56 optical bands, 8000 sqdeg TELESCOPE: 2.2m Javalambre (Teruel) CAMERA: JPCam, 5 sqdeg, 1.2Gpix DATES: Data acquisition begins 3Q2014 BONUS: 300M galaxies, QSOs, SNe, galaxy clusters, stars, over the whole area viernes 14 de diciembre de 2012

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51 CEFCA-Teruel: Mariano Moles, Javier Cenarro, David Cristóbal, Nicolás Gruel, Antonio Marín, Carlos Hernández-Monteagudo, Gustavo Bruzual IAA-Granada: Txitxo Benítez, Emilio Alfaro, Teresa Aparicio, Carlos Barceló, Rosa González, Javier Gorosábel, Matilde Fernández, Yolanda Jiménez-Teja Universidad de Valencia: Vicent Martínez, Pablo Arnalte, Juan Fabregat, Vicent Peris, Vicent Quilis IAC-Tenerife: Jordi Cepa, José Miguel Rodríguez-Espinosa, Angel Bongiovanni, José Alfonso López-Aguerri, Elena Ricci, Ignacio Trujillo, Alexander Vazdekis IFCA-Santander: Xavier Barcons, Enrique Martínez-González, Alberto Fernández-Soto, José María Diego, Ignacio González-Serrano, Patricio Vielva Universidad Complutense: Jesús Gallego, Javier Gorgas, Nicolás Cardiel Universidad Autónoma-Madrid: Patricia Sánchez-Blázquez, Gustavo Yepes CAB-Madrid: Álvaro Giménez, Eduardo Martín viernes 14 de diciembre de 2012

52 Universidad del País Vasco-Bilbao: Tom Broadhurst Universidad de Zaragoza: Antonio Elipe Universidad de Barcelona: Jordi Torra ESAC-Madrid: Enrique Solano Universidad de Florida: Rafa Guzmán JPAS in Brazil Renato Dupke, Raúl Abramo, Jailson Alcaniz, Bruno Castillo, Mauricio Calvão, Jorge Carvano, Roberto Cid-Fernandes, Eduardo Cypriano, Fabricio Ferrari, Claudia Mendes de Oliveira, Marcelo Rebouças, Thaisa Storchi-Bergman, Keith Taylor, Laerte Sodré, Joao Steiner, Eduardo Telles, Ioav Waga ~40+20 members for now viernes 14 de diciembre de 2012

53 The Science Behind (Benítez et al. 2009, Astrophysical Journal, 691, 241) Smearing of the BAO signal at different photometric redshift accuracy levels viernes 14 de diciembre de 2012

54 All of this will need a Telescope and a Camera... Enter the Observatorio Astrofisico de Javalambre (OAJ) viernes 14 de diciembre de 2012

55 JPCam Focal Plane JPCam T250 Telescope viernes 14 de diciembre de 2012

56 At the end of the day... Observational Cosmology relies heavily on cosmic surveys (thank God, the other one too!) Photometric redshift techniques are well established They can substitute the redshift machines There is big power in dedicated facilities Please stay tuned for these dates: December 2012: ALHAMBRA database goes public Summer 2013: T250 arrives at Javalambre Fall 2014: JPCam takes first observations viernes 14 de diciembre de 2012

57 Thank you!