Temporal evolution of the periodic GeV signal from 4FGL J1913.2+0512 and analysis of the SS 433 / W50 lobes

Clicks: 8
ID: 333644
2026
Free PDF
Article Quality & Performance Metrics
Overall Quality
Not rated
Combines reader engagement with the AI quality analysis. This article has not been analysed, so there is no overall score — reader engagement is measured and shown alongside.
AI Quality Assessment
Not analyzed
Readership in this journal
Emerging

Ranked #1,281 of 1,327 articles by views in monthly notices of the royal astronomical society

Most read Least read

Bar heights use a square-root scale. Only the 120 most-read articles are drawn; the journal has 1,327 in total.

Mint this article as an NFT
Not yet minted

Create a permanent, verifiable on-chain record of this article on the Scimatic Network. The NFT is held in your Journament account, and you can withdraw it to your own wallet at any time.

5 SUSD one-off · no wallet required
Sign in to mint
Abstract
Abstract SS 433 is a microquasar whose relativistic jets precess every ∼162 days, providing a laboratory for jet-interstellar medium interactions. We present a comprehensive analysis of 16 years of Fermi Large Area Telescope data (August 2008–September 2024) of the SS 433 / W50 field, using events in the 0.3 − 300 GeV range and employing pulsar gating to mitigate contamination from the bright nearby pulsar PSR J1907+0602. We detect the GeV source 4FGL J1913.2+0512 (TS = 45, where TS denotes the likelihood-ratio Test Statistic) with a power-law spectrum (photon index 2.61 ± 0.08) and confirm a GeV excess at the western lobe (TS = 17). The eastern lobe of SS 433 is hinted at with lower significance. One additional GeV excess, Fermi J1909.6+0552 (TS = 20; TS = 28 over 0.1 − 300 GeV), located outside the SS 433 / W50 system, is revealed after gating. Exposure-corrected Lomb-Scargle periodograms and precessional phase-folded light curves show a ∼162-day modulation in 4FGL J1913.2+0512. The phase-folded emission is mainly confined to the first half of the precessional cycle, while the source is not significantly detected in the second half. This periodic signal is mainly concentrated in the 5–10 yr interval, remains visible in the cumulative 0–10 yr dataset, and is not recovered in the subsequent 10–16 yr interval. Over the full 16-year dataset, the modulation remains detectable but with reduced significance, consistent with dilution by the later non-modulated epoch. These results indicate that the efficiency and/or geometry of gamma-ray production in the SS 433 environment evolves on multi-year timescales.
Reference Key
openalex_W7161582124 Use this key to autocite in the manuscript while using SciMatic Manuscript Manager or Thesis Manager
Authors Ömer Faruk Çoban, Diego F. Torres, Jian Li, Daniela Hadasch, Agnibha De Sarkar, Matthew T. Kerr
Are you one of these authors? Claim your profile
Journal monthly notices of the royal astronomical society
Year 2026
DOI
10.1093/mnras/stag2007
URL
https://doi.org/10.1093/mnras/stag2007
Keywords Keywords not found

Citations

No citations found. To add a citation, contact the admin at info@scimatic.org

Comments

No comments yet. Be the first to comment on this article.