The Breakthrough Listen Search For Intelligent Life Near the Galactic Center. I

Journal Article · Thu Jul 01 04:00:00 EDT 2021 · The Astronomical Journal (Online)

DOI:https://doi.org/10.3847/1538-3881/ABFD36· OSTI ID:23159283

Gajjar, Vishal; Siemion, Andrew P. V.; Foster, Griffin; Brzycki, Bryan; Chen, Yuhong; Croft, Steve; Czech, Daniel; DeBoer, David; DeMarines, Julia; Isaacson, Howard; Lacki, Brian C.; Lebofsky, Matt; MacMahon, David H. E.; Ng, Cherry ^[1]; Perez, Karen I. ^[2]; Chatterjee, Shami; Cordes, James M. ^[3]; Drew, Jamie ^[4]; Gowanlock, Michael ^[5]; others, and

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1. Department of Astronomy, University of California Berkeley, Berkeley, CA 94720 (United States)
2. Department of Astronomy, Columbia University, 550 West 120th Street, New York, NY 10027 (United States)
3. Cornell Center for Astrophysics and Planetary Science and Department of Astronomy, Cornell University, Ithaca, NY 14853 (United States)
4. The Breakthrough Initiatives, NASA Research Park, Boulevard 18, Moffett Field, CA 94035 (United States)
5. School of Informatics, Computing, and Cyber Systems, Northern Arizona University, Flagstaff, AZ 86011 (United States)

A line of sight toward the Galactic Center (GC) offers the largest number of potentially habitable systems of any direction in the sky. The Breakthrough Listen program is undertaking the most sensitive and deepest targeted SETI surveys toward the GC. Here, we outline our observing strategies with Robert C. Byrd Green Bank Telescope (GBT) and Parkes telescope to conduct 600 hr of deep observations across 0.7–93 GHz. We report preliminary results from our survey for extraterrestrial intelligence (ETI) beacons across 1–8 GHz with 7.0 and 11.2 hr of observations with Parkes and GBT, respectively. With our narrowband drifting signal search, we were able to place meaningful constraints on ETI transmitters across 1–4 GHz and 3.9–8 GHz with EIRP limits of ≥4 × 10{sup 18} W among 60 million stars and ≥5 × 10{sup 17} W among half a million stars, respectively. For the first time, we were able to constrain the existence of artificially dispersed transient signals across 3.9–8 GHz with EIRP ≥1 × 10{sup 14} W/Hz with a repetition period ≤4.3 hr. We also searched our 11.2 hr of deep observations of the GC and its surrounding region for Fast Radio Burst–like magnetars with the DM up to 5000 pc cm{sup -3} with maximum pulse widths up to 90 ms at 6 GHz. We detected several hundred transient bursts from SGR J1745–2900, but did not detect any new transient bursts with the peak luminosity limit across our observed band of ≥10{sup 31} erg s{sup -1} and burst rate of ≥0.23 burst hr{sup -1}. These limits are comparable to bright transient emission seen from other Galactic radio-loud magnetars, constraining their presence at the GC.

• OSTI ID: 23159283
• Journal Information: The Astronomical Journal (Online), Journal Name: The Astronomical Journal (Online) Journal Issue: 1 Vol. 162; ISSN 1538-3881
• Country of Publication: United States
• Language: English

Related Subjects

47 OTHER INSTRUMENTATION
79 ASTRONOMY AND ASTROPHYSICS
GHZ RANGE
LUMINOSITY
NEUTRON STARS
PULSES
SIGNALS
TELESCOPES
TRANSIENTS