Black-hole production at LHC: Special features, problems, and expectations
- PDF / 636,217 Bytes
- 9 Pages / 612 x 792 pts (letter) Page_size
- 33 Downloads / 180 Views
EMENTARY PARTICLES AND FIELDS Theory
Black-Hole Production at LHC: Special Features, Problems, and Expectations M. V. Savina* Joint Institute for Nuclear Research, Dubna, Moscow oblast, 141980 Russia Received May 28, 2010; in final form, July 29, 2010
Abstract—A brief survey of the present-day status of the problem of multidimensional-black-hole production at accelerators according to models featuring large extra dimensions is given. The respective production cross section and the Hawking temperature and decay rate are estimated versus model parameters. Possible flaws and assumptions whose accurate inclusion can reduce significantly the probability of blackhole production at accelerators in relation to earlier optimistic estimates are also discussed. DOI: 10.1134/S1063778811020190
Scenarios featuring large extra dimensions [1, 2] appeared more than ten years ago as an attempt at solving the scale-hierarchy problem associated with a formidable difference between the electroweak scale and the Planck mass MPl , which determines the limit of applicability of quantum field theory, where it gives way to quantum gravity. The reduction of the fundamental gravity scale from the value of 1019 GeV in four-dimensional theory to a much smaller value in multidimensional models is a feature peculiar to such models. This is due to considering a rather large volume of extra compact spatial dimensions (whose radius ranges between a micron and values of about 10−16 mm). In all such models, it is a multidimensional gravity scale rather than the four-dimensional Planck mass that is a fundamental quantity, and the same applies to the gravity couplings (in a more general case, to the couplings of all fields existing in the total multidimensional space). The four-dimensional gravitational constant becomes an effective constant related to the fundamental multidimensional constant through the volume and shape of the extra dimensions. The multidimensional energy scale may even become a value in the TeV region. In this case, effects of multidimensional physics may be observable at accelerators—in particular, at the Large Hadron Collider (LHC). This immediately entails a number of important implications. The first of these is the production of Kaluza–Klein excitations of those fields that are not localized in the three-dimensional brane. Owing to a high multiplicity [1] or owing to the geometry of the space [2], these *
E-mail: [email protected]
excitations are strongly coupled to ordinary matter, contributing to all particle-interaction processes, and this can be observed in accelerator experiments. The second implication has a direct bearing on the present study—this is the production of microscopic black holes at accelerators that is followed by their fast evaporation. Processes of this kind may become possible when the impact parameter of colliding particles (for example, protons in the case of LHC) becomes smaller than the Schwarzschild radius of a black hole whose mass corresponds roughly to the collision energy. This class of events is thought to
Data Loading...
