Astronomical Validation of the SRT Simona Righini, INAF-IRA – TD (Tecnologo III)

AV Team ¡  PS: Isabella Prandoni ¡  Co-PS: Matteo Murgia, Andrea Tarchi, Alessandro Orfei, Gianni Comoretto ¡  ~35 people covering technical/astronomical expertise (IRA – OAC – Arcetri):

Nichi D'Amico Andrea Orlati Simona Righini Roberto Ricci Sergio Poppi Alberto Pellizzoni Federica Govoni Tonino Pisanu Andrea Melis Carlo Migoni Silvia Casu Marta Burgay

Alessio Trois Antonietta Fara Paola Castangia Valentina Vacca Maria Noemi Iacolina Ignazio Porceddu Pietro Bolli Alessandro Corongiu Alessandra Zanichelli Carlo Stanghellini Francesco Nasyr Delphine Perrodin

Francesco Gaudiomonte Giuseppe Valente Elise Egron Caterina Tiburzi Alessandro Ridolfi Fabrizio Massi Raimondo Concu Marco Bartolini Marco Buttu Daria Guidetti Francesca Loi Matteo Bachetti

à Pulsar, Galactic & Extra-galactic, etc. à Continuum, Line, Mapping, VLBI, etc. à SW, Receivers, Backends, RFI, etc.

Active Surface: 1008 panels, 1116 remotely controlled electro-mechanical actuators

Largest Italian radio telescope (64 m) Quasi-Gregorian system with shaped surfaces

Multiple focal positions (P, G, 4 BWG): àup to 20 receivers in frequency agility

www.srt.inaf.it

Sardinia Radio Telescope

DFB: Digital Spectrometer (pulsar)

(ATNF Pulsar Digital Filter-Bank) 1 GHz BW, up to 16384 chan

ROACH boards: 2x512 MHz/1x1024 MHz

310-420 MHz 1.3-1.8 GHz 5.7-7.7 GHz Mono-feed 18-26.5 GHz Multi-feed 7 elements

Dual-band

DBBC2 (1 GHz, 4 IFs) + Mark5C (VLBI) + SW Corr (DIFX)

TP: analog Total Power 7x2 outputs, 2 GHz BW

XARCOS: Digital Spectrometer

8 outputs, 60 MHz BW, 4096 channels

Receivers and back-ends

Telescope Commissioning (closed: Oct. 2013) Advanced technical activities and precursors (started: Jan. 2014) “Fine-tuning”, integration of sub-systems (e.g. derotator), commissioning of additional backends (DFB, XARCOS, etc.), metrology, site monitoring, etc. Astronomical Validation (running in parallel, usually in evenings – 16-24)

Buildings: somewhere in 2015 Opening: Sept. 30, 2013

SRT Project Status

Last phase before first science-driven astronomical observations (shared-risk, early science)

¡ Goal 1: characterization of the SRT astronomical performance in all the standard observing modes; identification of technical problems and/or limitations;

¡ Goal 2: transformation of the instrument into a real Observatory (HW/SW development, observing/analysis tools, cook-book, etc.);

¡ Goal 3: maximization of science exploitation when made available

AV Goals

Outreach

Calibration campaigns

RFI (PRIN)

Documentation (e.g. User’s

guides)

Software Development

Commissioning and AV

Tests & Tools

(By the way…)

My main contributions (@ Medicina as well)

Fine Tuning and AV

AV “Grey-zone” TP tests

Measurement of the confusion noise: ~0.2 mJy/beam @ 7.3 GHz

Time (s/beam) Credits: S. Righini

Sort of “bridge” tests linking technical commissioning and “pure AV”. Goals: characterization of the TP backend, verification of On-The-Fly scans pointing accuracy and maximum exploitable speed, assessment of basic parameters of the SRT continuum capabilities, etc.

Verification of the back-end linearity range

RM

S n

oise

(m

Jy/b

ea

m)

Sou

rce

am

plit

ud

e (

co

un

ts)

Peak level (counts)

Observing with SRT: • ETC: SRT Exposure Time Calculator Zanichelli et al. • CASTIA: Source Visibility >30 telescopes (incl. EVN), on line Vacca, Iacolina et al. • ScheduleCreator Bartolini et al. Nuraghe SD Operations (TP/XARCOS) • SEADAS Corongiu et al. Interface for Pulsar Obs. (DFB/ROACH)

Data Monitoring/Handling: •  Cross-Scan Quick-Look/Reduction Righini et al. •  SDI: SD multi-feed Imager (OTF) Pellizzoni et al. •  RFI monitoring (DBBC) Melis et al. •  RFI detection/excision Ricci et al. •  Format Converters Trois et al. FITS to CLASS, etc.

Available on-line/SRT site

AV Software Tools

SRT 7 GHz 2.8’ res. June 2014 Medicina 5 GHz

6.4’ res.

Credits: SDI Team - A.Pellizzoni, E.Egron, M.N.Iacolina, S.Righini, A.Trois, V.Vacca

Imaging tests on SNR 3C157/IC 443 VLA 330 MHz 64”x74” resolution

(Hewitt et al. 2006)

Single-Dish Imager

(Pellizzoni et al. 2013)

TP

ROACH

SRT 7 GHz 2.8’ res. (test)

ADVANCED TEST: Observations with TP (C Band) to test/debug beam deconvolution procedures based on Imaging SW SCUBE (Govoni et al.): 300 maps of 3C147 Precursor: deep beam pattern measurements in various Elevation ranges

Credits: M. Murgia, F. Govoni, S.Poppi, V.Vacca, P.Castangia, A.Tarchi

3C147: Beam Model

High Dynamic Range Imaging

Credits: M. Murgia, F. Govoni, S.Poppi, V.Vacca, P.Castangia, A.Tarchi

3C147: Dirty Image Beam Model

Beam reconstruction and shapelet modeling are effective! è Dynamic Range ~ 7000 (and counting…)

High Dynamic Range Imaging

3C147: Cleaned Image

VALIDATED - CLOSE TO VALIDATION: ü VLBI Operations: first session (in shared risk) is ongoing (EVN+RadioAstron) L, C, K

ü LEAP Operations: L-band/Roach (close to ready)

ü Single Dish: Pulsar C-band Observations: TP and DFP folding mode; continuum TP observations: C-band, incl. imaging; K-band-single IN PROGRESS: ü Single Dish K-band-multifeed/imaging: Continuum TP

ü Single Dish Spectroscopy: single/multi-feed: XARCOS, ROACH boards

ü Single Dish Pulsar search mode CAVEAT: logistics, technical support (shifts), manpower…

AV Summary