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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').

200 results found.

  1. LIGO/Virgo G298048 GRAWITA: VST-ESO PARANAL follow up of AT2017gfo
  2. LIGO/Virgo G298048: Brightening X-ray Emission from GW170817/GRB170817A/SSS17a
  3. LIGO/Virgo G298048: Late-time detection of the X-ray afterglow with Chandra
  4. LIGO/Virgo G298048/GW170817: updated localization from parameter estimation
  5. LIGO/Virgo G298048: Mid-Infrared Spitzer/IRAC Observations at 3.6 and 4.5 microns
  6. LIGO/Virgo G298048: LWA radio observations
  7. LIGO/Virgo G298048: Record of all e-MERLIN results to date on SSS17a
  8. LIGO/Virgo G298048: Further European VLBI Network (EVN) observations of SSS17a
  9. LIGO/VIRGO G298048: VLA detection of the radio counterpart at 6 GHz
  10. LIGO/VIRGO G298048: Further MeerKAT observations of SSS17a
  11. LIGO/Virgo G298048: Summary of Pi of the Sky observations
  12. LIGO/VIRGO G298048: Latest 3 GHz Detection of Radio Counterpart to SSS17a
  13. LIGO/Virgo G298048: Limits from further FRB searches of SSS17a
  14. LIGO/Virgo G298048: MWA Observations of Error Region
  15. LIGO/Virgo G298048: Effelsberg 100-m Radio Telescope observations of SSS17a
  16. LIGO/Virgo G298048: SRT observations of SSS17a in NGC 4993
  17. LIGO/Virgo G298048: LCO FLOYDS and Gemini Spectroscopy
  18. LIGO/Virgo G298048: ATCA monitoring of SSS17a in NGC 4993
  19. LIGO/Virgo G298048: Limits from an FRB search of SSS17a with the Parkes 64m Radio Telescope
  20. LIGO/Virgo G298048: SSS17a photometry of CHILESCOPE observatory
  21. LIGO/Virgo G298048: Milliarcsecond imaging of the NGC 4993 central radio source
  22. LIGO/Virgo G298048: TOROS photometry of SSS17a
  23. LIGO/Virgo G298048: Desert Fireball Network simultaneous optical observations of the SSS17a/DLT17ck.
  24. LIGO/VIRGO G298048: MeerKAT observations of SSS17a
  25. LIGO/Virgo G298048: Danish Telescope Observations of SSS17a/DLT17ck
  26. LIGO/Virgo G298048: ATLAS pre-discovery limits 601 to 16 days before first detection of SSS17a/DLT17ck
  27. LIGO/Virgo G298048: AST3-2 observations of SSS17a/DLT17ck from Antarctica
  28. LIGO/Virgo G298048: ATCA monitoring of SSS17a in NGC 4993
  29. LIGO/Virgo G298048: VLA radio non-detection
  30. LIGO/Virgo G298048: VLBA upper limits at 8.7GHz for the GW counterpart SSS17a/DLT17ck on August 20-21 UT
  31. LIGO/Virgo G298048: LWA Detection
  32. LIGO/Virgo G298048: ATCA observations of of SSS17a in NGC 4993
  33. LIGO/Virgo G298048 GRAWITA: VST-ESO PARANAL follow up of SSS17a in NGC4993.
  34. LIGO/VIRGO G298048: Precise position of SSS17a based on HST and Gaia
  35. LIGO/VIRGO G298048: Radio detection of SSS17a at 6 GHz with the VLA
  36. LIGO/VIRGO G298048: Radio detection of SSS17a at 3GHz with the VLA/JAGWAR
  37. LIGO/Virgo G298048: e-MERLIN upper limits on 5 GHz compact emission from SSS17a
  38. LIGO/Virgo G298048: ATCA monitoring of SSS17a in NGC 4993
  39. LIGO/Virgo G298048: Chandra X-ray Update on GW170817
  40. LIGO/Virgo G298048: Chandra monitoring of the X-ray emission from SSS17a
  41. LIGO/Virgo G298048: Continued X-ray monitoring and X-ray detection of GW170817 [erratum]]
  42. LIGO/Virgo G298048: AGILE-GRID analysis of data contemporary to X-ray emission from SSS17a in NGC4993
  43. LIGO/Virgo G298048
  44. LIGO/Virgo G298048: Hubble Space Telescope observations
  45. LIGO/Virgo G298048: Possible Plateau in Ks band revealed by continued Gemini-South observations
  46. LIGO/Virgo G298048: Continued Gemini South observations
  47. LIGO/Virgo G298048: GMRT Follow-up of SSS17a at 1.4 GHz
  48. LIGO/Virgo G298048: Discovery of X-ray emission from SSS17a in NGC4993
  49. LIGO/Virgo G298048: European VLBI Network (EVN) upper limit on 5 GHz compact emission from SSS17a
  50. LIGO/Virgo G298048: OVRO 40m telescope follow-up
  51. LIGO/Virgo G298048: ALMA upper limits on 98 GHz emission from SSS17a
  52. LIGO/Virgo G298048: ALMA observations
  53. LIGO/Virgo G298048: Konus-Wind observations
  54. LIGO/Virgo G298048: Zadko Telescope 7 day observations of the OT candidate SSS17a/DLT17ck
  55. LIGO/Virgo G298048: Further ATCA follow-up of SSS17a in NGC 4993
  56. LIGO/Virgo G299232: Transient near NGC 1343 has a somewhat blue r-i color
  57. LIGO/Virgo G299232: Astrosat CZTI upper limits
  58. LIGO/Virgo G298048: uGMRT Follow-up of SSS17a at 400 MHz and 1.4 GHz
  59. LIGO/VIRGO G298048: INAF VST-ESO PARANAL observations of NGC4993
  60. LIGO/Virgo G299232: COINCIDENT IceCube neutrino observation UPDATE
  61. LIGO/Virgo G297595: INTEGRAL pointed follow-up observations
  62. LIGO/Virgo G298048: MASTER Global-Net early optical observations and the Possible KiloNova SSS17a in NGC 4993 photometry and merging rate
  63. LIGO/Virgo G298048: Pierre Auger Observatory neutrino follow-up
  64. LIGO/Virgo G298048: Subaru HSC z-band imaging of the OT candidate SSS17a
  65. LIGO/Virgo G298048: Near-infrared fading from Gemini-South
  66. LIGO/Virgo G298048: HAWC follow-up
  67. LIGO/Virgo G298048: Gemini-South Imaging and Spectroscopy
  68. LIGO/Virgo G298048: MUSE Integral Field Observations
  69. LIGO/Virgo G298048: LWA radio observations
  70. LIGO/VIRGO G298048: AAT/AAO spectroscopic observations of the GW counterpart candidate SSS17a/DLT17ck
  71. LIGO/Virgo G298048: LOFAR follow-up
  72. LIGO/Virgo G298048: H.E.S.S. very-high energy gamma-ray follow-up
  73. LIGO/Virgo G298048: INTEGRAL pointed follow-up observations
  74. LIGO/Virgo G298048: Results of the ASKAP search for fast radio bursts
  75. LIGO/Virgo G298048: ATCA follow-up of SSS17a in NGC 4993
  76. LIGO/Virgo G298048: Properties of NGC 4993
  77. LIGO/Virgo G298048: Continued VLA monitoring at 6 GHz
  78. LIGO/Virgo G298048: ESO/VLT optical observations
  79. LIGO/VIRGO G298048: VLA/JAGWAR observations of the CLU galaxies
  80. LIGO/Virgo G298048: Chandra X-ray observations
  81. LIGO/Virgo G298048: Global properties and star-formation rate of NGC 4993
  82. LIGO/Virgo G298048: observations of optical counterpart candidate with CHILESCOPE observatory
  83. LIGO/Virgo G298048: CALET Observations
  84. LIGO/Virgo G298048: ASKAP observations of SSS17a and NGC 4993 at 1.345 GHz
  85. LIGO/Virgo G298048: Gemini-South Near-Infrared Spectroscopy
  86. LIGO/Virgo G298048: MWA Observations of Error Region
  87. LIGO/Virgo G298048: VLA observation at 15 GHz
  88. LIGO/Virgo G298048: observations of optical counterpart candidate with CHILESCOPE observatory
  89. LIGO/Virgo G298048: TOROS Spectra observation with CASLEO
  90. LIGO/Virgo G298048: Pan-STARRS izy photometry of SSS17a/DLT17ck
  91. LIGO/Virgo G298048: Continued monitoring of the optical counterpart candidate
  92. LIGO/Virgo G298048 ANTARES search (2)
  93. LIGO/Virgo G298048: Correction to ATCA 8.5 GHz observations
  94. LIGO/Virgo G298048: ATCA 8.5 GHz observations of galaxies in the localisation volume
  95. LIGO/Virgo G298048: Zadko observations of the OT candidate SSS17a/DLT17ck
  96. LIGO/Virgo G298048: NuSTAR limits on X-ray emission
  97. LIGO/Virgo G298048: ASKAP follow up
  98. LIGO/Virgo G298048: optical observations with BOOTES-5 at San Pedro Mártir
  99. LIGO/Virgo G298048: Kanata/HONIR NIR photometry of the possible counterpart of G298048
  100. LIGO/Virgo G298048: On the kick velocity and age of the binary Neutron Stars Progenitor

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