Recent content by ofirg

Thanks For the reply. I see now that I mixed up the times that the telescopes will assign to the events themselves ( the time that the sources output the signal) which will be different And the time of observation, which will be the same.

I was just wondering. According to Lorentz transformations, if two events are simultaneous in one reference frame, they will generally not be simultaneous in another. The time difference that I get between the two events in the other reference frame is \Delta t^{`} = \gamma\beta\Delta x...

Its important to stress that this depends on the measurement your making. They cancel out when measuring the expansion rate of the universe ( via supernovae 1a ) But when measuring the angular scale of the peak in the CMB anisotropy spectrum (which depends on the spatial geometry of the universe...

I understand that by up and down quark you mean up type quark (t,c,u) and down type quark ( b,s,d). The answer is yes. The couplings of the W boson to any up type down type quark pair are described by the CKM matrix ( see http://pdg.lbl.gov/2014/reviews/rpp2014-rev-ckm-matrix.pdf for their...

What do you mean by that? What is and can be measured is the fraction of Nuclei that have decayed after a time T. Each Nuclei has either already decayed or not. A few clarifications. Each Nuclei decays independently at a time drawn from a distribution ( Exponential distribution). The half...

It would be beneficial to point to your reference. But I would imagine you're referring to a particle-anti particle pair after a C symmetry transformation. The (-1)^{L} factor comes from exchanging the particle coordinates in the spatial wave function after applying the C operator to return...

In the sense that it is not respected by some terms in the Lagrangian. The symmetry is only present when those terms are neglected.

The question seems to me to general. Due you have a more specific question? A few basics: Custodial symmetry is a symmetry that is respected by the SU(2) gauge interactions and the higgs self potential. It is not respected by the U(1) hypercharge interactions and yukawa terms for the fermions...

Unless someone knows otherwise, they are eigenstates of the third component of the weak isospin - T3 For example, the electric charge Q=T3+Y ( Y is the hypercharge) Since Y=0 in this case, Q=T3. So the states with well defined electric charge also have well defined and equal T3.

Actually, w\pm, w3 are the eigenstates of the weak isospin you are referring to ( which is the third component of the weak isospin - T3) The usefullness of the w1,2,3 basis is that it transforms as a vector in a three dimensional space.

You can't use a 70GeV trigger EtMiss requirement for a control region with EtMiss<100GeV at the oflline level. Most of your events would not pass the trigger. You have to look for a different trigger for these events in the control region. It can be a prescaled trigger if need be.

The total number of events are normalised by \frac{\sigma_{NNLO}}{\sigma_{LO/NLO}}

The Meaning on that statement is that the total number of events is normalized to the calculated NNLO inclusive cross section. The production itself is done at a lower order (LO or NLO), so the shapes of all the distrubutions reflect these lower orders. But the total normalization is...

A symmetric mass (or hermitian in the complex case) can have negative eigenvalues just not complex values. Because they are scalars they will mix with the higgs doublet scalars. There fermionic partners would mix with the fermionic partners of the higgs doublet scalars (higgsinos) It is in...

I don't think it is a typo. The physical mass is of course positive, but the neutralino mass matrix can have negative eigenvalues. Well, they consider an extension to the MSSM with an addition of a Standard Model singlet. The A1 and H1 in the table are the pseudoscalar and scalar which are...