Date: 2020 July 16 UTC Observers: Pogge (OSU), Wood (ND), & Olga Kuhn (LBTO) Remote Participants: Garnavich & Emami (ND), Smirnov & Vincenzo (OSU) Special Assistants: Bentley & Trim TO: David Gonzalez (LBTO) SA: Olga Kuhn Moon phase: gray (moonrise @ midnight) Summary: Good night overall, and first good OSURC night in a long while. Program was all MODS observing, mostly long-slit and one MOS field. Completed 5 high-priority targets including some with ~2h visits given the mostly clear conditions, indications of haze later, satellite at sunset suggests i is high-elevation smoke from California fires. Good seeing from 0.8-1” at the start to episodes of 0.5-0.6”. See detailed notes below. Programs: OSU_ASASSN - ASASSN20hx ND_carbon - HE2123-0329 OSU_CHAOS - NGC6946 Field 1 OSU_Lithium - BrownDwarf3 ND_j0053 - J0053 Flux calibration stars (BD+284211 & G191B2B) Details (All times UT): ---------------------- 02:21 Slewed to BD+28 4211 acqBinoMODS bd284211.acq mods1r 0007: offsetxy -0.264 10.948 rel based on 0008, tweaked -0.289 0.167 rel mods2r 0001: offsetxy 4.163 6.988 rel based on confirmatory image 0002, needs a tweak: -0.826 -0.163 rel given execBinoMODS bd284211_dualred.obs to obtain dual and red-only spectra. mods1r: dual 10-12, 13-15 mods2r: dual 04-06, 07-09 the guide signal is rock steady but the allsky worried us… it just looks blurry. 02:55 end of 18-deg twilight 02:55 slewing to OSU_ASASSN 2020hx acqBinoMODS ASASSN20hx.acq seeing is ~0.9" mods1r 16 and 17: offsetxy -0.435 11.040 rel 18 was off to the right, gave a dx = -0.18" rel offset mods2r 10 and 11: offsetxy 3.653 7.404 rel 12 looked good execBinoMODS ASASSN20hx.obs 03:27 seeing on SX GCS is ~0.7" and on DX GCS ~0.9" mods1r: 19…21 mods1b: 10…12 mods2r: 13…15 mods2b: 04...06 04:00 We have been puzzling over the source of some light that we've noticed on the allsky images, mostly lighting up the trees to the SE and the SMT building. Bruce went to the utility building and VATT to investigate - there was a porch light on and some interior lights. At 04:12, the allsky no longer shows any source of light. 04:22 OSU_ASASSN done 04:22 slewing to ND_carbon he2123-0329 acqBinoMODS he2123-0329_pa155.acq on guider, SX seeing ~0.7" and DX seeing ~ 0.09" mods1r: 22 and 23: offsetxy -0.037 10.402 rel mods2r: 16 and 17: offsetxy 4.534 6.561 rel execBinoMODS he2123-0329 started these spectra will be dual grating with the 0.6" slit. mods1r: 25…27 mods1b: 13…15 mods2r: 19…21 mods2b: 07...09 05:03 slewing to N6946F1 acqBinoMODS N6946F1.acq on guider, SX seeing 0.56", DX seeing 0.67" mods1r: 28 and 29: offsetpointing -0.1687 -0.959 0.749 detxy rel 30 looks good mods2r: 22 and 23: offsetpointing -0.0400 3.515 -1.575 detxy rel 24 looks good 05:20 execBinoMODS N6946F1.obs 06:20, during 3rd of 6 exposures, the FWHM is 0.8" on both sides 06:37, the guide star FWHM are ~0.75" and temperature gradients across primaries (Radial diff) are <0.01 deg C. mods1r: 31...36 mods1b: 16...21 mods2r: 25...30 mods2b: 10...15 07:32 Slewing to OSU_Lithium BrownDwarf3 acqBinoMODS BD3.acq This will be a tricky acquisition: the science slit is 1", but there is a hugely bright star near the target and we used the PointingMask to block it in the field image. In order to run modsAlign on the slit+field image pair, the header of the field image will need to be edited to set MASKPOS = "STOW" It proceeded fairly well, except that the PointingMask was selected but not inserted by the script (a slitmask command within an acq script resulted in an mselect only, not an minsert). Because the minsert was not done (the mask was at STOW), MASKPOS did not need to be edited in the headers this time. mods1r: 37(1") and 38 (PointingMask) offsetxy 4.488 17.801 rel based on the confirmatory image, 39, we needed to tweak it by dX = -0.3". In the next image, 40, the star looks well-centered. mods2r: 31(1") and 32 (PointingMask) offsetxy 8.731 14.227 rel The star looks well-centered on the confirmatory thru-slit image 33. 07:55 execBInoMODS BD3.obs red-only, 1" slit 6x1200 sec exposures or until the object is too close to the zenith. FWHM of guider images ~0.7" near the start, improving to 0.51"/0.59" on SX/DX at 09:30 UT at 09:45 we noticed that the guide signals have been very slowly dropping throughout this series of exposures, by almost 1 magnitude. We don't see clouds on the all-sky but there does appear to be some haze. at 09:52, 89 deg elevation, we started to notice that the centroid of the guide star is drifting away from the hot spot. We lost the preset on MODS1 and stopped the exposure (47) with about 400 s remaining. The preset on MODS2 was not lost. The guide star drifted from the hotspot, about 1" at times, but came back after the object had transited. mods1r: 41…46 mods2r: 34…39 10:00 quit and restarted the MODS1 Red IC 10:06 Slewing to ND_j0053 acqBinoMODS j0053_pa-40.acq m1r: 47 and 48: offsetxy 0.013 10.426 rel On the confirmatory slit image, 49, the target is to the right. We tweaked it by dX = -0.2" and it looks well-centered on 50. m2r: 40 and 41: offsetxy 4.423 6.343 rel The confirmatory slit image, 42, looked good, but the target was just a bit to the right. We tweaked it by dX = -0.1" and since it was such a small adjustment, we did not take a second through-slit image. 10:19 execBInoMODS j0053.obs time-series observation (5 x 540-sec) On SX, the FWHM ~ 0.65" but on DX, FWHM ~ 1.00". We don't understand why the DX FWHM has been worse tonight, except for a short period of time. m1r: 51...55 (on 52 and 54, there were delays of 100-sec between close-of-shutter and the start of the readout) m1b: 22...26 m2r: 43...47 m2b: 16...20 11:19 Slewing to G191-B2B acqBinoMODS g191b2b.acq mods1r 56: offsetxy 0.016 10.801 rel On 57, the star looks well-centered. mods2r 48: offsetxy 5.187 6.764 rel It needed an additional offset based on 49: offsetxy -0.729 -0.132 rel execBinoMODS g191b2b_dualred.obs 11:34 FWHM on guide stars is now similar on both SX and DX, ~0.8". mods1r: dual 58-60 and red-only 61-63 mods1b: dual 27-29 mods2r: dual 50-52 and red-only 53-55 mods2b: dual 21-23 11:58 David is closing up.