اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدHiding a Heavy Higgs Boson at the 7 TeV LHC
242
0
0.0
(
0
)
اسأل ChatGPT حول البحث
ﻻ يوجد ملخص باللغة العربية
A heavy Standard Model Higgs boson is not only disfavored by electroweak precision observables but is also excluded by direct searches at the 7 TeV LHC for a wide range of masses. Here, we examine scenarios where a heavy Higgs boson can be made consistent with both the indirect constraints and the direct null searches by adding only one new particle beyond the Standard Model. This new particle should be a weak multiplet in order to have additional contributions to the oblique parameters. If it is a color singlet, we find that a heavy Higgs with an intermediate mass of 200 - 300 GeV can decay into the new states, suppressing the branching ratios for the standard model modes, and thus hiding a heavy Higgs at the LHC. If the new particle is also charged under QCD, the Higgs production cross section from gluon fusion can be reduced significantly due to the new colored particle one-loop contribution. Current collider constraints on the new particles allow for viable parameter space to exist in order to hide a heavy Higgs boson. We categorize the general signatures of these new particles, identify favored regions of their parameter space and point out that discovering or excluding them at the LHC can provide important indirect information for a heavy Higgs. Finally, for a very heavy Higgs boson, beyond the search limit at the 7 TeV LHC, we discuss three additional scenarios where models would be consistent with electroweak precision tests: including an additional vector-like fermion mixing with the top quark, adding another U(1) gauge boson and modifying triple-gauge boson couplings.
قيم البحث
اقرأ أيضاً
The search for heavy Higgs bosons is an essential step in the exploration of the Higgs sector and in probing the Supersymmetric parameter space. This paper discusses the constraints on the M(A) and tan beta parameters derived from the bounds on the d
ifferent decay channels of the neutral H and A bosons accessible at the LHC, in the framework of the phenomenological MSSM. The implications from the present LHC results and the expected sensitivity of the 14 TeV data are discussed in terms of the coverage of the [M(A) - tan beta] plane. New channels becoming important at 13 and 14 TeV for low values of tan beta are characterised in terms of their kinematics and the reconstruction strategies. The effect of QCD systematics, SUSY loop effects and decays into pairs of SUSY particles on these constraints are discussed in details.
The 19/20-parameter p(henomenological)MSSM with either a neutralino or gravitino LSP offers a flexible framework for the study of a wide variety of R-parity conserving MSSM SUSY phenomena at the 7, 8 and 14 TeV LHC. Here we present the results of a s
tudy of SUSY signatures at these facilities obtained via a fast Monte Carlo replication of the ATLAS SUSY analysis suite. In particular, we show the ranges of the sparticle masses that are either disfavored or remain viable after all of the various searches at the 7 and 8 TeV runs are combined. We then extrapolate to 14 TeV with both 300 fb^-1 and 3 ab^-1 of integrated luminosity and determine the sensitivity of a jets + MET search to the pMSSM parameter space. We find that the high-luminosity LHC performs extremely well in probing natural SUSY models.
We study the Higgs boson $(h)$ decay to two light jets at the 14 TeV High-Luminosity-LHC (HL-LHC), where a light jet ($j$) represents any non-flavor tagged jet from the observational point of view. The decay mode $hto gg$ is chosen as the benchmark s
ince it is the dominant channel in the Standard Model (SM), but the bound obtained is also applicable to the light quarks $(j=u,d,s)$. We estimate the achievable bounds on the decay branching fractions through the associated production $Vh (V=W^pm,Z)$. Events of the Higgs boson decaying into heavy (tagged) or light (un-tagged) jets are correlatively analyzed. We find that with 3000 fb$^{-1}$ data at the HL-LHC, we should expect approximately $1sigma$ statistical significance on the SM $Vh(gg)$ signal in this channel. This corresponds to a reachable upper bound ${rm BR}(hto jj) leq 4~ {rm BR}^{SM}(hto gg)$ at $95%$ confidence level. A consistency fit also leads to an upper bound ${rm BR}(hto cc) < 15~ {rm BR}^{SM}(hto cc)$ at $95%$ confidence level. The estimated bound may be further strengthened by adopting multiple variable analyses, or adding other production channels.
If the fundamental Planck scale is near a TeV, then TeV scale black holes should be produced in proton-proton collisions at the LHC where sqrt{s} = 14 TeV. As the temperature of the black holes can be ~ 1 TeV we also expect production of Higgs bosons
from them via Hawking radiation. This is a different production mode for the Higgs boson, which would normally be produced via direct pQCD parton fusion processes. In this paper we compare total cross sections and transverse momentum distributions dsigma/dp_T for Higgs production from black holes at the LHC with those from direct parton fusion processes at next-to-next-to-leading order and next-to-leading order respectively. We find that the Higgs production from black holes can be larger or smaller than the direct pQCD production depending upon the Planck mass and black hole mass. We also find that dsigma/dp_T of Higgs production from black holes increases as a function of p_T which is in sharp contrast with the pQCD predictions where dsigma/dp_T decreases so we suggest that the measurement of an increase in dsigma/dp_T as p_T increases for Higgs (or any other heavy particle) production can be a useful signature for black holes at the LHC.
We discuss production of charm and bottom quarks at forward rapidity in pp collisions at the LHC, updating the QCD predictions for the run at sqrt{S}=13 TeV. We show that, while the absolute rates suffer from large theoretical systematics, dominated
by scale uncertainties, the increase relative to the rates precisely measured at 7 TeV can be predicted with an accuracy of a few percent, sufficient to highlight the sensitivity to the gluon distribution function.
سجل دخول لتتمكن من نشر تعليقات
التعليقات
جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
