# Physics Commons™

Selected Works

High energy physics phenomenology

Publication

Articles 1 - 5 of 5

## Full-Text Articles in Physics

Direct Photons As Probes Of Low Mass Strings At The Lhc, Luis Anchordoqui, Haim Goldberg, Satoshi Nawata, Tomasz Taylor Feb 2011

#### Direct Photons As Probes Of Low Mass Strings At The Lhc, Luis Anchordoqui, Haim Goldberg, Satoshi Nawata, Tomasz Taylor

##### Tomasz Taylor

The LHC program will include the identification of events with single prompt high-k_\perp photons as probes of new physics. We show that this channel is uniquely suited to search for experimental evidence of TeV-scale open string theory. At the parton level, we analyze single photon production in gluon fusion, gg \to \gamma g, with open string states propagating in intermediate channels. If the photon mixes with the gauge boson of the baryon number, which is a common feature of D-brane quivers, the amplitude appears already at the string disk level. It is completely determined by the mixing parameter (which ...

Direct Photons As Probes Of Low Mass Strings At The Lhc, Luis Anchordoqui, Haim Goldberg, Satoshi Nawata, Tomasz Taylor Feb 2011

#### Direct Photons As Probes Of Low Mass Strings At The Lhc, Luis Anchordoqui, Haim Goldberg, Satoshi Nawata, Tomasz Taylor

##### Haim Goldberg

The LHC program will include the identification of events with single prompt high-k_\perp photons as probes of new physics. We show that this channel is uniquely suited to search for experimental evidence of TeV-scale open string theory. At the parton level, we analyze single photon production in gluon fusion, gg \to \gamma g, with open string states propagating in intermediate channels. If the photon mixes with the gauge boson of the baryon number, which is a common feature of D-brane quivers, the amplitude appears already at the string disk level. It is completely determined by the mixing parameter (which ...

Electric Dipole Moments And Polarizability In The Quark-Diquark Model Of The Neutron, Y. Srivastava, A. Widom, J. Swain, O. Panella Feb 2011

#### Electric Dipole Moments And Polarizability In The Quark-Diquark Model Of The Neutron, Y. Srivastava, A. Widom, J. Swain, O. Panella

##### Allan Widom

For a bound state internal wave function respecting parity symmetry, it can be rigorously argued that the mean electric dipole moment must be strictly zero. Thus, both the neutron, viewed as a bound state of three quarks, and the water molecule, viewed as a bound state of ten electrons two protons and an oxygen nucleus, both have zero mean electric dipole moments. Yet, the water molecule is said to have a nonzero dipole moment strength $d=e\Lambda$ with $\Lambda_{H_2O} \approx 0.385\ \dot{A}$. The neutron may also be said to have an electric dipole moment strength with ...

Black Holes From Cosmic Rays: Probes Of Extra Dimensions And New Limits On Tev-Scale Gravity, Luis Anchordoqui, Jonathan Feng, Haim Goldberg, Alfred Shapere Jan 2011

#### Black Holes From Cosmic Rays: Probes Of Extra Dimensions And New Limits On Tev-Scale Gravity, Luis Anchordoqui, Jonathan Feng, Haim Goldberg, Alfred Shapere

##### Haim Goldberg

If extra spacetime dimensions and low-scale gravity exist, black holes will be produced in observable collisions of elementary particles. For the next several years, ultra-high energy cosmic rays provide the most promising window on this phenomenon. In particular, cosmic neutrinos can produce black holes deep in the Earth’s atmosphere, leading to quasi-horizontal giant air showers. We determine the sensitivity of cosmic ray detectors to black hole production and compare the results to other probes of extra dimensions. With n ≥ 4 extra dimensions, current bounds on deeply penetrating showers from AGASA already provide the most stringent bound on low-scale gravity ...

Concerning The Differences Between Zero Mass Dirac And Zero Mass Majorana Neutrinos, Y. Srivastava, A. Widom Jan 2011

#### Concerning The Differences Between Zero Mass Dirac And Zero Mass Majorana Neutrinos, Y. Srivastava, A. Widom

##### Allan Widom

That a Majorana neutrino theory is different from a Dirac neutrino theory (even in the zero mass limit) is proved in two sentences.