Related papers: Mass ambiguities in cascade decays
We derive analytical expressions for the shape of the invariant mass distributions of massless Standard Model endproducts in cascade decays involving massive New Physics (NP) particles, D -> Cc -> Bbc -> Aabc, where the final NP particle A…
The classic method for mass determination in a SUSY-like cascade decay chain relies on measurements of the kinematic endpoints in the invariant mass distributions of suitable collections of visible decay products. However, the procedure is…
In SUSY scenarios with invisible LSP, sparticle masses can be determined from fits to the endpoints of invariant mass distributions. Here we discuss possible improvements by using the shapes of the distributions. Positive results are found…
The measurements of kinematical endpoints, in cascade decays of supersymmetric particles, in principle allow for a determination of the masses of the unstable particles. However, in this procedure ambiguities often arise. We here illustrate…
A simple method is proposed for determining the masses of new particles in collider events containing a pair of decay chains (not necessarily identical) of the form Z -> Y+1, Y -> X+2, X -> N+3, where 1,2 and 3 are visible but N is not.…
We consider the mass measurement at hadron colliders for a decay chain of two steps, which ends with a missing particle. Such a topology appears as a subprocess of signal events of many new physics models which contain a dark matter…
We consider the decay of a generic resonance to two visible particles and any number of invisible particles. We show that the shape of the invariant mass distribution of the two visible particles is sensitive to both the mass spectrum of…
Mass measurement of a particle whose decay products including invisible particles is a challenging task at colliders. For a new physics model involving a dark matter candidate $N$ and a $Z_2$ symmetry that stabilizes it, a typical new…
We show that mass measurements for new particles appearing in decay chains can be improved by determining the boundary of the available phase space in its full dimensionality rather than by using one-dimensional kinematic features for each…
Considering the cascade decay $D\to c C \to c b B \to c b a A$ in which $D,C,B,A$ are massive particles and $c,b,a$ are massless particles, we determine for the first time the shape of the distribution of the invariant mass of the three…
We discussed in arXiv:1209.0772 that the laboratory frame distribution of the energy of a massless particle from a two-body decay at a hadron collider has a peak whose location is identical to the value of this daughter's (fixed) energy in…
Motivated by evidence for the existence of dark matter, many new physics models predict the pair production of new particles, followed by the decays into two invisible particles, leading to a momentum imbalance in the visible system. For…
If the LHC is able to produce dark matter particles, they would appear at the end of cascade decay chains, manifesting themselves as missing transverse energy. However, such "dark matter candidates" may decay invisibly later on. We propose…
Formulae are derived for the positions of end-points in the invariant mass and transverse mass distributions obtained from the products of heavy states decaying to pairs of semi-invisibly decaying lighter states. Formulae are derived both…
A method is proposed for determining the masses of the new particles N,X,Y,Z in collider events containing a pair of effectively identical decay chains Z to Y+jet, Y to X+l_1, X to N+l_2, where l_1, l_2 are opposite-sign same-flavour…
If R-parity conserving supersymmetry exists below the TeV-scale, new particles will be produced and decay in cascades at the LHC. The lightest supersymmetric particle will escape the detectors, thereby complicating the full reconstruction…
Energy distributions of decay products carry information on the kinematics of the decay in ways that are at the same time straightforward and quite hidden. I will review these properties and discuss their early historical applications as…
We revisit the method of kinematical endpoints for particle mass determination, applied to the popular SUSY decay chain squark -> neutralino -> slepton -> LSP. We analyze the uniqueness of the solutions for the mass spectrum in terms of the…
A straightforward new technique is introduced which enables measurement at hadron colliders of an analytical combination of the masses of pair-produced semi-invisibly decaying particles and their invisible decay products. The new technique…
We present an improved method of reconstructing New Physics (NP) masses from invariant mass endpoints. While the traditional method focuses on a single NP decay, our method considers the decays of two or more NP particles ($ABC...$) in a…