Constraining the variation of fundamental constants using 18cm OH lines
| dc.creator | Chengalur, Jayaram N. | |
| dc.creator | Kanekar, Nissim | |
| dc.date | 2003-10-27 | |
| dc.date.accessioned | 2026-07-07T10:47:44Z | |
| dc.date.available | 2026-07-07T10:47:44Z | |
| dc.description | We describe a new technique to estimate variations in the fundamental constants using 18cm OH absorption lines. This has the advantage that all lines arise in the same species, allowing a clean comparison between the measured redshifts. In conjunction with one additional transition (for example, an HCO$^+$ line), it is possible to simultaneously measure changes in $α$, $g_p$ and $y \equiv m_e/m_p$. At present, only the 1665 MHz and 1667 MHz lines have been detected at cosmological distances; we use these line redshifts in conjunction with those of HI 21cm and mm-wave molecular absorption in a gravitational lens at $z\sim 0.68$ to constrain changes in the above three parameters over the redshift range $0 < z \lesssim 0.68$. While the constraints are relatively weak ($\lesssim$ 1 part in $10^3$), this is the first simultaneous constraint on the variation of all three parameters. We also demonstrate that either one (or more) of $α$, $g_p$ and $y$ must vary with cosmological time or there must be systematic velocity offsets between the OH, HCO$^+$ and HI absorbing clouds. | |
| dc.description | 5 pages, no figures. Accepted for publication in Phys. Rev. Lett | |
| dc.identifier | https://arxiv.org/abs/astro-ph/0310764 | |
| dc.identifier | http://arxiv.org/abs/astro-ph/0310764 | |
| dc.identifier | Phys.Rev.Lett.91:241302,2003 | |
| dc.identifier | doi:10.1103/PhysRevLett.91.241302 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/183639 | |
| dc.subject | Astrophysics | |
| dc.subject | High Energy Physics - Theory | |
| dc.subject | Atomic Physics | |
| dc.title | Constraining the variation of fundamental constants using 18cm OH lines | |
| dc.type | text |