KVN Single-dish Test Observations of the KVN Yonsei telescope at 22/43 GHz - Performance of KVN Yonsei telescope at 22/43GHz Sang-Sung Lee March 18, East Asia VLBI Workshop

KVN Collaboration  Do-Young Byun – Field System management  Do-Heung Je – Receiver System management  Seog-Tae Han – Quasi Optics management  Tomoharu Kurayama – DAS management  Se-Jin Oh – DAS and Clock System management  Kee-Tae Kim, Bong Won Sohn – Observation plan  Advisors: Hyunsoo Chung, Se-Hyung Cho, Duk-Gyoo Roh, Chang Hoon Lee, Bong Gyu Kim

KVN Outline  Introduction  Test observations of KVN  Goals of single-dish test observations  Observations and results  System setup  First light and Simultaneous observations  Pointing model at 22GHz  Beam alignment measurements  Aperture Efficiencies  Discussion  Outlook

KVN Introduction  Test observations of KVN in  100-GHz Acceptance observations (K. T. Kim’s talk)  Single-dish test observations at 22/43GHz (This talk)  VLBI test observations btw KVN-VERA (B. W. Sohn’s talk)  Goals of single-dish test observations  Performance test of KVN telescopes at 22, 43, 86 and 129GHz Pointing model Aperture efficiencies  Feasibility test of multi-frequency simultaneous observations Beam alignment measurements (S. T. Han’s talk) Instrumental phase stability measurements (D. H. Je’s poster)

KVN Receiver Cabin System setup Observation Building 43 GHz FE 22 GHz FE Down Converter Receiver systemDASClockField system GUI Control PC 1 pps Distributor 100 MHz Distributor 10 MHz Distributor 10 MHz Distributor 1 pps Distributor 5 MHz 10 MHz 100 MHz 1 pps 1.4 GHz Clock System H-maser GPS Digital O/E WDM Optical MUX Digital E/O Sampler WDM Optical DMUX Digital Spectro- meter Mark5B DIR-1000 Digital Filters Down Converter Sampler

KVN First lights of KVN Yonsei telescope 22GHz First light from H 2 O masers in W49N at 22GHz on Aug Digital spectrometer with wideband mode BW = 512MHz

KVN First lights of KVN Yonsei telescope 43GHz First light from SiO masers in Orion KL at 43GHz on Aug Digital spectrometer with narrow band mode 1 BW = 256MHz

KVN Simultaneous observations at 22/43 GHz of KVN Yonsei telescope Simultaneous observations at 22/43GHz for thermal emission (Venus) on Oct Two power-streams at 22 and 43 GHz while OTF scanning Venus

KVN Simultaneous observations at 22/43 GHz of KVN Yonsei telescope Simultaneous observations at 22/43GHz for maser emission (Orion KL) on Oct

KVN Pointing model at 22 GHz Six maser sources : W49N, OrionKL, VY CMa, WB755, W3OH, Cep A Observations on Sep RMS error of the pointing model : 4” in AZ, 5” in EL

KVN 22/43GHz beam alignment measurements  Goals: 7" of beam offsets btw 22/43GHz  10% of FWHM (70") at 129GHz  Beam alignment K/Q bands Jupiter  Beam offset from 1 st measurement (Jupiter): (∆AZ, ΔEL)=(1.6", 22")(∆AZ, ΔEL)=(1.6", 30° in EL Orion KLNo dependency on EL (found by observing Orion KL with FIVE Points) Adjusting Rx-direction by 2 degrees on the Rx plate Jupiter  Beam offset from 2 nd measurement (Jupiter): (ΔAZ, ΔEL)=(1.6", -2.9")(ΔAZ, ΔEL)=(1.6", 30° in EL Within pointing accuracy of 5" and our goal of 7 " Orion KL  Beam offsets from 3 rd measurement (Orion KL): at various ELs of 14 ° ~ 47 ° with the optimized sub-reflector model (, )=(4.2", -0.6")(, )=(4.2", -0.6")

KVN Beam offsets from 3rd measurement (Orion KL): H2O masers (at 22 GHz) and SiO maser (at 43GHz) at various ELs of 14 ° ~ 47 ° and various AZs of 90 ° ~ 210 ° with the optimized sub-reflector model (, )=(4.2", -0.6")

KVN Aperture efficiencies Frequencies Planets Aperture eff. (%) EL (°) HPBW (“) T B (K) 22GHzJupiter6430LPF * Venus6830LPF ** 43GHzJupiter64.430LPF270150*** Venus68.832LPF *** * : Page et al ApJS 148, 39 ** : Butler et al Icarus 154, 226 *** : Greve et al A&A 286, 654 Sub-reflector was optimized in position. Aperture efficiencies are values of single measurements.

KVN Discussion and Outlook  Discussion  Why is the beam offsets btw K/Q dependant in AZ of observations? Position difference of H2O and SiO masers in Orion KL? –( ), ( ) System deformation in AZ but not in EL? Uncertainty of position of Orion KL?

KVN Discussion and Outlook  Outlook  Receivers at 22/43GHz taken down after the observations.  100-GHz acceptance tests done for KVN YS.  Receivers at 22/43GHz set up again on Feb  need to confirm the results from the previous observations  Beam alignment test for planet revisited (S. T. Han’s talk)  Beam alignment test for Orion KL to be revisited  Double check of pointing model to be done  Polarization characteristic should be measured  Gain curve measurements  After confirming all the characteristics, we will start single-dish observations of KVN Yonsei.