Astrophysical and cosmological implications of large volume string compactifications

By Joseph P. Conlon, F. Quevedo. 2007

134 citations recorded by the source corpus.

We study the spectrum, couplings and cosmological and astrophysical implications of the moduli fields for the class of Calabi–Yau IIB string compactifications for which moduli stabilisation leads to an exponentially large volume and an intermediate string scale ms∼1011 GeV, with TeV-scale observable supersymmetry breaking. All Kähler moduli except for the overall volume are heavier than the susy (supersymmetry) breaking scale, with m∼ln(MP/m3/2)m3/2∼(ln(MP/m3/2))2msusy∼500 TeV and, contrary to standard expectations, have matter couplings suppressed only by the string scale rather than the Planck scale. These decay to matter early in the history of the universe, with a reheat temperature T∼107 GeV, and are free from the cosmological moduli problem (CMP). The heavy moduli have a branching ratio to gravitino pairs of 10−30 and do not suffer from the gravitino overproduction problem. The overall volume modulus is a distinctive feature of these models and is an Mplanck-coupled scalar of mass m∼1 MeV and subject to the CMP. A period of thermal inflation may help relax this problem. This field has a lifetime τ∼1024 s and can contribute to dark matter. It may be detected through its decays to γγ or e+e−. If accessible the e+e− decay mode dominates, with suppressed by a factor (ln(MP/m3/2))2. We consider the potential for detection of this field through different astrophysical sources: the Milky Way halo, the diffuse cosmic background and nearby galaxy clusters and find that the observed gamma ray background constrains . The decays of this field may generate the 511 keV emission line from the galactic centre observed by INTEGRAL/SPI.

Subfields: Astronomy and Astrophysics, Nuclear and High Energy Physics

View Paper: https://www.semanticscholar.org/paper/9e29efd334ee4aae75d2d721c17aa6bd7328d572

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Astronomy and Astrophysics

In Nuclear and High Energy Physics

Citations in the corpus

Systematics of string loop corrections in type IIB Calabi-Yau flux compactifications (2007, background): “field theory, whereas the local modes couple at the string scale [ 21 ].”
Lyman-alpha constraints on warm and on warm-plus-cold dark matter models (2008, background): “There are many examples of super-WIMP DM models: sterile neutrinos [15], gravitinos in theories with broken R-parity [37, 38], light volume moduli [39] or Majorons [40].”
The type IIB string axiverse and its low-energy phenomenology (2012, unknown): “their initial displacement is tiny [46].”
The POEMMA (Probe of Extreme Multi-Messenger Astrophysics) observatory (2020, background): “One example involves cosmic neutrinos produced via the decay of highly boosted, strongly coupled moduli — scalar fields — radiated by relic cosmic strings [131], which are quite generic in the string theory landscape [132, 133].”
Non-Thermal Dark Matter and the Moduli Problem in String Frameworks (2008, background): “The cosmological moduli/gravitino problems and adequate generation of dark matter within the Type IIB frameworks has met with some mixed success in a recent paper [29].”
Towards universal axion inflation and reheating in string theory (2014, methodology): “For this purpose [21] we have to diagonalize the action”
Phenomenology of a pseudo-scalar inflaton: naturally large nongaussianity (2011, background): “See [71, 72] for a discussion of axion/moduli couplings and decays in large volume inflationary scenarios.”
General analysis of LARGE Volume Scenarios with string loop moduli stabilisation (2008, background): “A proper analysis of their couplings to photons along the lines of [24] should be made in order to see if this effect could be eventually detected.”