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7th US VLBI Technical Meeting at Haystack Observatory, November 3-4, 2009 Arecibo VLBI Report Arecibo VLBI Team: V. Arun, R. Ganesan, T. Ghosh, C. Salter Arecibo Observatory (National Astronomy & Ionosphere Center)
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7th US VLBI Technical Meeting at Haystack Observatory, November 3-4, 2009 Receivers 800
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7th US VLBI Technical Meeting at Haystack Observatory, November 3-4, 2009 Existing Arecibo VLBI Capability DAR - VLBA4 MK5A Max 1-GHz IF The Big Dish (Gain~10k/Jy,SEFD~3-5 Jy) Correlator Internet FedEx 1024 Mbps256 MHz (max) 2 x 8, 16 MHz.05,.5 (#1,2 Rxs), 1 GHz 327, 800, L, S-Lo, S- High, C, C-High, X Total data rateTotal single-pol RF Bandwidth # of BBCs & Max ∆ν/BBC Max. IF bandwidth/Rx Receivers Co-Observing Networks: 1.VLBA + Ar & the HSA (HSA, includes the phased-VLA, GBT, EF) 2. European VLBI Network + Ar 3. Global - Network 4. eVLBI (Real-time VLBI via internet: as yet with the EVN only)
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7th US VLBI Technical Meeting at Haystack Observatory, November 3-4, 2009 Progress Since Last US VLBI Tech Meeting Regular participation in e-EVN operations up to 512 Mbit/sec. Imminent acquisition of a 12-m VLBI Phase- referencing antenna using NSF stimulus funds. Two Mark-5C recorders have been purchased and received at Arecibo. Two digital back-ends (DBEs) are on order and delivery is expected by the end of the year.
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7th US VLBI Technical Meeting at Haystack Observatory, November 3-4, 2009 The Arecibo 12-m Antenna Current Status – O rder to be placed for a Patriot 12-m antenna in the coming days. The antenna should arrive at the Observatory in Jan/Feb 2010, with assembly in March. When commissioned, it will primarily be used for VLBI phase referencing. Freq. Coverage – An S/X receiver has been ordered from Patriot Antenna Systems Inc. This will be supplemented later by C- (and L-band) systems. It is intended that a broadband system will eventually be installed. Single Dish Uses – Education and research applications with Puerto-Rican universities and other educational establishments. Other Uses – (a) Participation in VLBI2010; (b) At L-band, the voltage beam-width of a 12-m antenna contains all seven beams of the ALFA receiver, opening up a possibility of multi-beam interferometric applications.
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7th US VLBI Technical Meeting at Haystack Observatory, November 3-4, 2009 The Arecibo 12-m Antenna Site The Arecibo 12-m Antenna Site 12-m Antenna Site The AUT Patriot 12-m Antenna
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7th US VLBI Technical Meeting at Haystack Observatory, November 3-4, 2009 eVLBI: Test Run at 512-Mbit/sec First trans-Atlantic eVLBI fringes at a data rate of 512 Mbits/sec on 9 September 2008. Fulfills an ExPRES project milestone. Data arriving at JIVE Arecibo Fringes with EVN Telescopes Between 12 midnight and 6 a.m. data rates of 512 Mbits/sec are possible, with a rate of 256 Mbit/sec being available at other times. Data leaving Arecibo
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7th US VLBI Technical Meeting at Haystack Observatory, November 3-4, 2009 Arecibo eVLBI Astronomy Observing time = 2 hr. Antennas = Cm, Kn, Jb2, Mc, On, Tr & Wb. Observing time = 8 hr. Antennas = Cm, Da, Jb1, Mc, On, Tr, Ef & Ar (for 2 hr 20 min.) 1.6 GHz; J1218+2953 5 GHz Image of J0204+151 made during the IYA “24 hours of eVLBI” by Ar plus 16 other telescopes on 5 continents, 5 GHz ToO observations of SS433 made between November 6 & 19, 2008.
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7th US VLBI Technical Meeting at Haystack Observatory, November 3-4, 2009 Arecibo’s Funding Future Current Cooperative agreement between Cornell & NSF ends in March 2010. Likely extension of six months. NSF expected to issue its RFP for Arecibo recompetition soon. Cornell is actively pursuing management partners and alternate funding sources The NSF Senior Review recommendation for post-2010 was to reduce AST funding from $8M to $4M. PR Government is contributing $3M through a bond issue. NAIC is receiving $3M under the “Obama Stimulus Package” to NSF; this is funding the purchase of the 12-m VLBI antenna.
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7th US VLBI Technical Meeting at Haystack Observatory, November 3-4, 2009 Muchas Gracias desde Puerto Rico
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A continuum observation, =18-cm, data-rate=512 Mbps, i.e. 128 MHz of RF bandwidth, dual-polarization, = 120 minutes on source: Arecibo’s Contribution to the Arrays A spectral-line observation, =18-cm, 64 channels over 1-MHz, 2 pol, 120mins. 0.25 mJy/beam/ch 0.62 3.00.310.9 mJy/beam/ch VLBA+Y27+Gb+ARVLBA+Y27+GBVLBAEVN+AREVN 1σ Image noise = 2.5 μJy/beam 4.7 μJy/beam Global (EVN+VLBA+Y27+Gb)+Ar -Ar 1σ Image noise = 3.8 μJy/beam 9 μJy/beam EVN+Ar -Ar 1σ Image noise = 3.3 μJy/beam 7.1 μJy/beam HSA (VLBA+Y27+EF+GB+Ar) -Ar
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7th US VLBI Technical Meeting at Haystack Observatory, November 3-4, 2009 Possible Upgrade Path (1) Get a VDBE system that Steve Durand was offering for our 305-m dish, and a Mark5C + 10G ethernet. (2) Keep the old analog rack and Mark5A operational for as long as EVN needs it (until they switch over to software correlator). (3) Get a replica of VLBI2010 backend (DBE2) and recorder for the 12-m telescope. The biggest unknown (to TG) for this scenario is if the data form the 12-m and 305-m will be correlatable at Socorro with all other VLBA antennas (and in between themselves) for phase-referenced observations, were we to chose the above option. By the time, the 12-m comes on line, EVN might have moved to software correlator so that the same question will be applicable for the JIVE correlator as well
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