دورية أكاديمية

Quasar outflow deceleration or acceleration: predictions and a search.

التفاصيل البيبلوغرافية
العنوان: Quasar outflow deceleration or acceleration: predictions and a search.
المؤلفون: Hall, P B1 (AUTHOR) phall@yorku.ca, Weiss, E1 (AUTHOR), Brandt, W N2,3,4 (AUTHOR), Mulholland, C J1 (AUTHOR)
المصدر: Monthly Notices of the Royal Astronomical Society. 3/15/2024, Vol. 528 Issue 4, p6496-6516. 21p.
مصطلحات موضوعية: *ACCELERATION (Mechanics), *INTERSTELLAR medium, *QUASARS, *ACTIVE galaxies, *GALACTIC evolution, *FORECASTING
مستخلص: Quasar winds can shock and sweep up ambient interstellar medium (ISM) gas, contributing to galactic quenching. We combine and extend past models of energy-conserving shock bubbles around quasars, investigate model implications from an observational standpoint, and test model predictions using new high-resolution spectroscopic observations of the broad absorption-line quasar SDSS J030000.56+004828.0 (J0300). Even with constant energy input from the wind, a bubble's expansion decelerates over time as more ISM gas is swept up. Our new observations enable a direct search for this deceleration. We obtain the tightest reported 3σ limit on the average rest-frame deceleration (or acceleration) of a quasar outflow: | a | < 0.1 km s−1 yr−1 (<3 × 10−4 cm s−2) in the relatively low-velocity Ca  ii outflow of J0300 over 9.65 rest-frame years. We can satisfy these limits with certain parameter choices in our model, but the large velocity range of the Ca  ii absorption in J0300 rules out the hypothesis that such gas shares the velocity of the swept-up ISM gas in a self-similar shock bubble. We investigate the possibility of ram-pressure acceleration of preexisting ISM clouds and conclude that the velocity range seen in Ca  ii in J0300 is potentially consistent with such an explanation. The Ca  ii -absorbing gas clouds in J0300 have been inferred to have high densities by Choi et al. in which case they can only have been accelerated to their current speeds if they were originally at least an order of magnitude less dense than they are today. [ABSTRACT FROM AUTHOR]
قاعدة البيانات: Academic Search Index
الوصف
تدمد:00358711
DOI:10.1093/mnras/stae330