1. PY 2010 NAIC Progress Report & Program Plan Review 2nd December 2010 Radio Astronomy: Other Projects Chris Salter Arecibo Observatory (National Astronomy & Ionosphere Center) ‏

2. PY 2010 NAIC Progress Report & Program Plan Review 2nd December 2010 Arecibo Astronomy Observing Details -- 57% of passive astronomy telescope time for large (≥300 hr) survey projects: currently all using ALFA or LBW receivers. -- 43% of passive astronomy telescope time for other (PI) astronomical studies (72 projects). -- Frequency coverage: 327, 430 & 800 MHz, 1.1-10 GHz via 6 receivers + ALFA. For PY 2009;

3. PY 2010 NAIC Progress Report & Program Plan Review 2nd December 2010 Pulsar Highlights Timing of binary pulsar PSR J1738+0333 provides the most constraining limit yet on dipolar gravitational wave emission. It also excludes all TeVeS (Tensor-Vector-Scalar) theories, the relativistic version of MOND. This reaffirms the existance of dark matter. Of 9 new Fermi γ-ray pulsars in the Arecibo sky, J1907+0602 is found to be a radio pulsar (P=0.10664 s). With a flux of S 1.4 GHz = 3 μJy, and a distance ~ 3 kpc, it is the second least luminous pulsar known! The young, energetic radio/X-ray pulsar, PSR J1930+1852 (P=0.136 s), which is situated within the supernova remnant, SNR G54.1+0.3, has had its braking index detemined to be 1.941± 0.001. Arecibo Timing and γ-Ray Pulsars Msec-period PSR J2043+1710 was discovered at Nançay coincident with a compact unidentified Fermi source. This PSR is too weak to measure accurately anywhere but Arecibo, whose timing enabled phase-folding of the Fermi/LAT data, revealing γ-ray pulsations.

4. PY 2010 NAIC Progress Report & Program Plan Review 2nd December 2010 High Time Resolution PSR Observations Full-Stokes, single-pulse observations of “normal” pulsars with ~50 μs time reso lution. T rec = 590 μs PSR B1929+10 T rec = 59 μs PSR B2020+28 T rec = 59 μs Find multiple substructures of μsec duration that are almost 100% linearly polarized. Indicates emission regions of size ≤ 15 km. The 305-m dish is the only radio telescope capable of detecting such substructures in the single pulses of “normal” pulsars. Mitra & Rankin suggest that with even higher time resolution would likely reveal even finer coherent temporal structure.

5. PY 2010 NAIC Progress Report & Program Plan Review 2nd December 2010 Apparent > c Wave Propagation in the ISM The group velocity of the ISM is > c near the HI resonance line due to “anomalous dispersion”. The plot above shows the expected absorption and delay spectra after propagation through a cloud of HI in the ISM with T S = 100 K, τ = 1. HI Emission Spectrum PSR Absorption Spectrum PSR Delay Spectrum Delay Spectra for 3 Consecutive Days Potential tool for studying the HI properties of the ISM. (Note: It does NOT violate Special Relativity!)

6. PY 2010 NAIC Progress Report & Program Plan Review 2nd December 2010 Red Dwarf “Pulsars” A number of ultra-cool dwarf stars have been observed at Arecibo displaying similarities between the pulses measured. Example of TVLM 513-46546 (left) and 2MASSW J0746425+200032 (right) in Stokes-V. Pulses have brightness temperature > 10 15 K. For electron cyclotron maser emission, magnetic field strengths of ~1650 Gauss are implied. Simultaneous Arecibo, Hα, optical photometry, and NIR spectrophometry of TVLM 513, show in-phase variations for radio, Hα, [OI] and the optical continuum.

7. PY 2010 NAIC Progress Report & Program Plan Review 2nd December 2010 HI Forbidden-Velocity Wings LDS b=−0.5° HVC 004-6: Arecibo (LBW and ALFA) + GBT observations of 22 FVWs. 12-13 show shell-type structure; “missing” SNRs? 9-10 show cloud-type structure; halo clouds or HVCs? FVW's 173.0+3.0 & 173.0+0.0: Red = +45 – +35 km/s, Green = +35 – +25 km/s, Blue = +25 – +15 km/s. The HI emission coincides with a weak continuum shell. FVW G39.0+4.0: Red = +110 – +135 km/s, Green = +95 – 110 km/s, Blue = +80 – +95 km/s. Stars = Early-type stars in field; Triangles = Pulsars

8. PY 2010 NAIC Progress Report & Program Plan Review 2nd December 2010 An Arecibo Galactic Chemistry Survey To exploit the low “spectral line confusion” for 1 – 10 GHz to characterize the physical and chemical conditions in Galactic sources. Precursor observations made in 2008 on star-forming region, NGC2264, and C-rich, evolved PPN, CRL618. These were shallow 1 – 10 GHz coverages with Δv = 0.7 kms -1. Main survey commenced in 2010 studying W51e2 with Δv = 0.3 kms -1. Excited satellite line OH maser in PPN, CRL 618 CH 3 OH in NGC 2264-IRS1 HC 3 N in NGC 2264-IRS1 H112α in W51e2 H 2 13 CO and H141β in W51e2 H141β H 2 13 CO H 2 CO in W51e2 Excited Satellite OH in W51e ( 2 Π ½ J=½ F=0–1) ‏

9. PY 2010 NAIC Progress Report & Program Plan Review 2nd December 2010 HI Absorption at z ~ 0.9 HI absorption in the host galaxy of CTA 21 against the continuum emission of the central quasar Observed at Arecibo on 20 & 21 September 2009  Observed at Arecibo on 20 & 21 September 2009  Redshift, z = 0.906  Distance = 5866 Mpc  CTA 21 is seen at 46% of the present age of the Universe Central Frequency = 745.5 MHz Analog-to-Digital migration of TV transmissions in June 2009 temporarily freed up the 700–800 MHz band. Arecibo has provided and commissioned a receiver. HI absorption in the host galaxy of 4C+15.05 against the continuum emission of the central quasar  Observed at Arecibo on 3, 4 & 5 October 2010  Redshift, z = 0.833  Distance = 5283 Mpc  Resolves optical disagreement between z=0.405 and 0.833 Central Frequency = 780.4 MHz

10. H 2 CO at 4830 MHz OH at 4660 MHz OH at 4751 MHz OH at 4766 MHz HCN at 4488 MHz CH 2 NH at 5290 MHz Arecibo Spectra for Zw 049.057 Molecular Lines in Luminous IR Galaxies

11. Arecibo Spectra for NGC660 Variable Excited OH Masers at 4751 & 4766 MHz (Excited OH Line at 4660 MHz is below noise.)‏ H 2 CO at 4830 MHz 25 Dec 07 – 07 Jan 08 7 Aug 08 – 10 Sep 08 24 Dec 08 Co-added RRLs H109α–H114α (λ6 cm)‏; rms noise = 70 μJy/beam

12. PY 2010 NAIC Progress Report & Program Plan Review 2nd December 2010 An H 2 O Maser at z = 2.64 H 2 O maser detected in the gravitationally-lensed quasar MG J0414+0534 at Effelsberg. Monitored at Arecibo each 6 weeks for 15 months from Oct. 2008. Line profile is very stable, with velocity drift of line peak < 2 kms -1 yr -1. Main line blue shifted relative to systemic velocity favors association of the maser with the relativistic jet. If confirmed, tentative red-shifted line at +470 kms -1 would favor a disk- situated maser.

13. PY 2010 NAIC Progress Report & Program Plan Review 2nd December 2010 Arecibo VLBI Highlights – 2010 Continued HSA, EVN and Global Array operations. eVLBI science runs at 256 & 512 Mbit/sec. Acquisition, construction and infrastructure development for the 12-m VLBI phase-reference dish. Acquisition of 2 × Mark-5C recorders, and the imminent delivery of 2 × digital back-ends (RDBEs). The High Sensitivity Array (HSA) The EVN

14. PY 2010 NAIC Progress Report & Program Plan Review 2nd December 2010 e-VLBI: Monitoring the M87 Jet during a TeV Outburst Optical HST image of M87 Jet and a knot of hot gas, HST-1, seen to be brightening in 2005, with subsequent TeV outbursts. Superluminal motion (V app ~2.7c) in HST-1 during a TeV outburst The inner Jet (collimated for ~200 mas) and the weaker complex, HST-1 (at 800 mas from the core), imaged at 5-GHz, with resolution 7 x 3 mas, and map noise of 0.12 mJy/beam. Nov19 Jan27 Feb10 Nov1 9 Mar02 Mar30

15. PY 2010 NAIC Progress Report & Program Plan Review 2nd December 2010 VLBI Sensitivity Upgrade Increasing the US VLBI data recording rate to at least 4 Gbps by 2010 was a goal set by the Taylor Committee (2004). Arecibo is in the process of: 1. Increasing the Recorded Bandwidth : (a) Replacing our analog DAR with a Digital Back End (RDBE). Arecibo has ordered two RDEs from NRAO, and delivery is expected by the year end. (b) Upgrading to the Mark5C recording system. Arecibo has purchased and received two Mark5C units from Conduant Corp. Control software is under development at Haystack and will be installed in our units there. 2. Increasing the Integration Time: The low 305-m antenna slew rate can lead to >50% loss of integration time in phase-referenced VLBI. The new Arecibo 12-m dish will track the phase- calibrator continually, while the 305-m tracks the target, just occasionally visiting the calibrator. Phases derived from the 12-m data will be applied to the 305-m data under the assumption that the same ionospheric corrections apply to both data sets.

16. PY 2010 NAIC Progress Report & Program Plan Review 2nd December 2010 The Arecibo 12-m Antenna The Arecibo 12-m Antenna 12-m Antenna Site The Arecibo 12-m Patriot Antenna Access Road (then nearing completion)‏

17. PY 2010 NAIC Progress Report & Program Plan Review 2nd December 2010 The Arecibo 12-m Antenna Why 12-m?: A 12-m antenna provides a baseline sensitivity within a factor of 2 of a VLBA dish. Sources brighter than ~110 mJy can be used for phase referencing. Frequency Coverage: L, S, C & X bands are required for astronomy with the 305-m dish; S/X bands are being installed initially. Thereafter, a 1 – 12 GHz multi-frequency front end is anticipated. Other Potential Uses: (a) Possible participation in regular VLBA operations, (b) VLBI2010; (c) The L-band, voltage beamwidth of the 12-m antenna contains all 7 ALFA beams, opening up the possibility of multi-beam interferometric applications, (d) Education and research applications with Puerto-Rican universities and other educational establishments. (“Science with the 12-m Workshop”: May 2010)

18. PY 2010 NAIC Progress Report & Program Plan Review 2nd December 2010 Anticipated Developments over PY 2011 Continued development towards a 40-beam focal-plane phased feed array to give an HI mapping array with the observing speed of ASKAP or MeerKAT. Developments towards replacing the present four receivers covering 2 to 8 GHz with two broader-band systems. Developments towards bringing the RF signals directly to the Control Room. Completion of VLBI equipment upgrade to a digital backend and Mk5C recorders allowing regular recording at up to 4 Gbits/sec. Implementation of the VLBI “phase transfer” methodology from the 12-m calibration data to the 305-m target data.

19. PY 2010 NAIC Progress Report & Program Plan Review 2nd December 2010 Muchas Gracias

20. PY 2010 NAIC Progress Report & Program Plan Review 2nd December 2010 VLBI Sensitivity Upgrade Increasing the US VLBI data recording rate to at least 4 Gbps by 2010 was a goal set by the Taylor Committee. 1. Increasing the Bandwidth : Arecibo is in the process of: (a) replacing the analog DAR with a Digital Back End (RDBE). - The Digital Down Conversion (DDC) personality consists of four independently tunable sub-bands per IF, with bandwidths 0.5 - 256 MHz and 1–8 bit output sample precision. There is also a Polyphase Filter Bank (PFB) personality with 32 sub-bands spanning the 500-MHz wide IF. Output is via 10-Gbit Ethernet transporting individual sub-band packet streams. Maximum data rate of 8 Gbps. Arecibo has ordered two RDEs from NRAO. (b) upgrading to the Mark5C recording system developed by Haystack & Conduant Corp. Control software is still under development at Haystack. Arecibo has purchased and received two Mark5C units.

21. PY 2010 NAIC Progress Report & Program Plan Review 2nd December 2010 2. Increasing the Integration Time VLBI is severely limited by ionospheric and tropospheric phase fluctuations, leading to a loss of coherence. As a solution, many VLBI observations these days are taken in “Phase referenced” mode. The most commonly used form of this mode needs slewing between the target and a strong, compact calibration source (generally within a few degrees of the target) every 3-4 min. Phase, derived from the calibrator, is then applied to the target data. The low slew rate of 305-m antenna can lead to over 50% loss of integration time in phase-referenced VLBI.

22. PY 2010 NAIC Progress Report & Program Plan Review 2nd December 2010 Receivers 800

23. PY 2010 NAIC Progress Report & Program Plan Review 2nd December 2010 The Three Little Pigs (PI: Josh Goldston Peek)‏ Tiny clouds found at b ≈ 85°; Δθ ≈ 1'. VLA follow-up shows condensed cores, optically-thick, with T B ≈ 10K. Arecibo measures Magnetic Field strength ~14 μG → 200 – 800 times the magnetic pressure of the WIM. Upper limits on OH emission from Arecibo. Now Pigs by the Drove! (Ayesha Begum & Snezana Stanimirovic) About 100 compact, cold clouds, isolated from Galactic emission in a limited area of the TOGS/TOGS2 survey. Median angular size ~5', T b ~ 0.7 K, FWHM ~ 4.2 km/s, and N HI ~ 5 × 10 18 cm -2. Clouds deviate from Galactic rotation by 10 – 40 km/s, and evidence for multiphase medium and velocity gradients.

24. PY 2010 NAIC Progress Report & Program Plan Review 2nd December 2010 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)‏

25. PY 2010 NAIC Progress Report & Program Plan Review 2nd December 2010 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, 120 min. 0.25 mJy/beam/ch 0.62 3.00.310.9 mJy/beam/ch VLBA+Y27+Gb+ARVLBA+Y27+GBVLBAEVN+AREVN HSA (VLBA+Y27+EF+GB+Ar)‏ -Ar 1σ Image noise = 3.3 μJy/beam 7.1 μJy/beam EVN+Ar -Ar 1σ Image noise = 3.8 μJy/beam 9 μJy/beam Global (EVN+VLBA+Y27+Gb)+Ar -Ar 1σ Image noise = 2.5 μJy/beam 4.7 μJy/beam

26. PY 2010 NAIC Progress Report & Program Plan Review 2nd December 2010 Operational block diagram (evolving)