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Theory Advances in BSM Physics
http://cds.cern.ch/record/2148845
Rather than attempting to summarise the full spectrum of recent advances in Beyond the Standard Model (BSM) theory, which are many, in this talk I will instead take the opportunity to focus on two frameworks related to the hierarchy problem currently receiving significant attention. They are the `Twin Higgs' and the `Relaxion'. I will summarise the basic underlying structure of these theories at a non-expert level and highlight some interesting phenomenological signatures or outstanding problems.McCullough, MatthewWed, 27 Apr 2016 05:44:12 GMT25 Apr 2016arXiv:1604.07184http://cds.cern.ch/record/2148845['arXiv:1604.07184']arXiv:1604.07184Charm in Deep-Inelastic Scattering
http://cds.cern.ch/record/2148652
We show how to extend systematically the FONLL scheme for inclusion of heavy quark mass effects in DIS to account for the possible effects of an intrinsic charm component in the nucleon. We show that when there is no intrinsic charm, FONLL is equivalent to S-ACOT to any order in perturbation theory, while when an intrinsic charm component is included FONLL is identical to ACOT, again to all orders in perturbation theory. We discuss in detail the inclusion of top and bottom quarks to construct a variable flavour number scheme, and give explicit expressions for the construction of the structure functions $F^c_2$, $F^c_L$ and $F^c_3$ to NNLO.Ball, Richard DBonvini, MarcoRottoli, LucaWed, 27 Apr 2016 05:38:59 GMT08 Oct 2015arXiv:1510.02491http://cds.cern.ch/record/2148652['arXiv:1510.02491']arXiv:1510.02491The Standard Model Higgs as the origin of the hot Big Bang
http://cds.cern.ch/record/2146161
If the Standard Model (SM) Higgs is weakly coupled to the inflationary sector, the Higgs is expected to be universally in the form of a condensate towards the end of inflation. The Higgs decays rapidly after inflation -- via non-perturbative effects -- into an out-of-equilibrium distribution of SM species, which thermalize soon afterwards. If the post-inflationary equation of state of the universe is stiff, $w \simeq +1$, the SM species eventually dominate the total energy budget. This provides a natural origin for the relativistic thermal plasma of SM species, required for the onset the `hot Big Bang' era. The viability of this scenario requires the inflationary Hubble scale $H_*$ to be lower than the instability scale for Higgs vacuum decay, the Higgs not to generate too large curvature perturbations at cosmological scales, and the SM dominance to occur before Big Bang Nucleosynthesis. We show that successful reheating into the SM can only be obtained in the presence of a non-minimal coupling to gravity $\xi \gg 0.1$, with a reheating temperature $T_{\rm RH} \simeq \mathcal{O}(10^{10})\xi^{3/2}(H_*/10^{14}{\rm GeV})^2~{\rm GeV}$Figueroa, Daniel GByrnes, Christian TFri, 15 Apr 2016 05:54:43 GMT13 Apr 2016arXiv:1604.03905http://cds.cern.ch/record/2146161['arXiv:1604.03905']arXiv:1604.03905Large $N$ topologically twisted index: necklace quivers, dualities, and Sasaki-Einstein spaces
http://cds.cern.ch/record/2145743
In this paper, we calculate the topological free energy for a number of ${\mathcal N} \geq 2$ Yang-Mills-Chern-Simons-matter theories at large $N$ and fixed Chern-Simons levels. The topological free energy is defined as the logarithm of the partition function of the theory on $S^2 \times S^1$ with a topological A-twist along $S^2$ and can be reduced to a matrix integral by exploiting the localization technique. The theories of our interest are dual to a variety of Calabi-Yau four-fold singularities, including a product of two asymptotically locally Euclidean singularities and the cone over various well-known homogeneous Sasaki-Einstein seven-manifolds, $N^{0,1,0}$, $V^{5,2}$, and $Q^{1,1,1}$. We check that the large $N$ topological free energy can be matched for theories which are related by dualities, including mirror symmetry and $\mathrm{SL}(2,\mathbb{Z})$ duality.Hosseini, Seyed MortezaMekareeya, NoppadolWed, 13 Apr 2016 06:29:22 GMT12 Apr 2016arXiv:1604.03397http://cds.cern.ch/record/2145743['arXiv:1604.03397']arXiv:1604.03397Track 3: Computations in theoretical physics -- techniques and methods
http://cds.cern.ch/record/2145715
Here, we attempt to summarize the activities of Track 3 of the 17th International Workshop on Advanced Computing and Analysis Techniques in Physics Research (ACAT 2016).Luisoni, GionataPoslavsky, StanislavSchroder, YorkWed, 13 Apr 2016 06:28:33 GMT12 Apr 2016arXiv:1604.03370http://cds.cern.ch/record/2145715['arXiv:1604.03370']arXiv:1604.03370Thoughts on heavy-ion physics in the high luminosity era: the soft sector
http://cds.cern.ch/record/2145710
This document summarizes thoughts on opportunities in the soft-QCD sector from high-energy nuclear collisions at high luminosities.Antinori, FedericoBecattini, FrancescoBraun-Munzinger, PeterChujo, TatsuyaHamagaki, HidekiHarris, JohnHeinz, UlrichHippolyte, BorisHirano, TetsufumiJacak, BarbaraKharzeev, DmitriLoizides, ConstantinMasciocchi, SilviaMilov, AlexanderMorsch, AndreasMüller, BerndtNagle, JamieOllitrault, Jean-YvesPaic, GuyRajagopal, KrishnaRoland, GuntherSchukraft, JürgenSchutz, YvesSnellings, RaimondStachel, JohannaTeaney, DerekVelkovska, JuliaVoloshin, SergeiWiedemann, Urs AchimXu, ZhangbuZajc, WilliamWed, 13 Apr 2016 06:28:32 GMT12 Apr 2016arXiv:1604.03310http://cds.cern.ch/record/2145710['arXiv:1604.03310']arXiv:1604.03310Three-Index Symmetric Matter Representations of SU(2) in F-Theory from Non-Tate Form Weierstrass Models
http://cds.cern.ch/record/2144181
We give an explicit construction of a class of F-theory models with matter in the three-index symmetric (4) representation of SU(2). This matter is realized at codimension two loci in the F-theory base where the divisor carrying the gauge group is singular; the associated Weierstrass model does not have the form associated with a generic SU(2) Tate model. For 6D theories, the matter is localized at a triple point singularity of arithmetic genus g=3 in the curve supporting the SU(2) group. This is the first explicit realization of matter in F-theory in a representation corresponding to a genus contribution greater than one. The construction is realized by "unHiggsing" a model with a U(1) gauge factor under which there is matter with charge q=3. The resulting SU(2) models can be further unHiggsed to realize non-Abelian G_2xSU(2) models with more conventional matter content or SU(2)^3 models with trifundamental matter. The U(1) models used as the basis for this construction do not seem to have a Weierstrass realization in the general form found by Morrison-Park, suggesting that a generalization of that form may be needed to incorporate models with arbitrary matter representations and gauge groups localized on singular divisors.Klevers, DenisTaylor, WashingtonWed, 06 Apr 2016 05:57:35 GMT04 Apr 2016arXiv:1604.01030http://cds.cern.ch/record/2144181['arXiv:1604.01030']arXiv:1604.01030Single and double inclusive forward jet production at the LHC at $\sqrt{s}$ = 7 and 13 TeV
http://cds.cern.ch/record/2144161
We provide a description of the transverse momentum spectrum of single inclusive forward jets produced at the LHC, at the center-of-mass energies of 7 and 13 TeV, using the high energy factorization (HEF) framework. We subsequently study double inclusive forward jet production and, in particular, we calculate contributions to azimuthal angle distributions coming from double parton scattering. We also compare our results for double inclusive jet production to those obtained with the Pythia Monte Carlo generator. This comparison confirms that the HEF resummation acts like an initial state parton shower. It also points towards the need to include final state radiation effects in the HEF formalism.Bury, MarcinDeak, MichalKutak, KrzysztofSapeta, SebastianWed, 06 Apr 2016 05:56:54 GMT05 Apr 2016arXiv:1604.01305http://cds.cern.ch/record/2144161['arXiv:1604.01305']arXiv:1604.01305Stop searches in flavourful supersymmetry
http://cds.cern.ch/record/2144103
Natural realisations of supersymmetry require light stops ${\tilde t}_1$, making them a prime target of LHC searches for physics beyond the Standard Model. Depending on the kinematic region, the main search channels are ${\tilde t_1}\to t \tilde \chi^0_1$, ${\tilde t_1}\to W b \tilde \chi^0_1$ and ${\tilde t_1}\to c \tilde \chi^0_1$. We first examine the interplay of these decay modes with ${\tilde c_1}\to c \tilde \chi^0_1$ in a model-independent fashion, revealing the existence of large regions in parameter space which are excluded for any ${\tilde t_1}\to c \tilde \chi^0_1$ branching ratio. This effect is then illustrated for scenarios with stop-scharm mixing in the right-handed sector, where it has previously been observed that the stop mass limits can be significantly weakened for large mixing. Our analysis shows that once the LHC bounds from ${\tilde c_1}\to c \tilde \chi^0_1$ searches are taken into account, non-zero stop-scharm mixing leads only to a modest increase in the allowed regions of parameter space, with large areas excluded for arbitrary mixing angles.Crivellin, AndreasHaisch, UlrichTunstall, Lewis CWed, 06 Apr 2016 05:55:13 GMT01 Apr 2016arXiv:1604.00440http://cds.cern.ch/record/2144103['arXiv:1604.00440']arXiv:1604.00440Radioactive Iron Rain: Transporting $^{60}$Fe in Supernova Dust to the Ocean Floor
http://cds.cern.ch/record/2143998
Several searches have found evidence of $^{60}$Fe deposition, presumably from a near-Earth supernova (SN), with concentrations that vary in different locations on Earth. This paper examines various influences on the path of interstellar dust carrying $^{60}$Fe from a SN through the heliosphere, with the aim of estimating the final global distribution on the ocean floor. We study the influences of magnetic fields, angle of arrival, wind and ocean cycling of SN material on the concentrations at different locations. We find that the passage of SN material through the mesosphere/lower thermosphere (MLT) is the greatest influence on the final global distribution, with ocean cycling causing lesser alteration as the SN material sinks to the ocean floor. SN distance estimates in previous works that assumed a uniform distribution are a good approximation. Including the effects on surface distributions, we estimate a distance of $46^{+10}_{-6}$ pc for a $8-10 \ M_{\odot}$ SN progenitor. This is consistent with a SN occurring within the Tuc-Hor stellar group $\sim$2.8 Myr ago with SN material arriving on Earth $\sim$2.2 Myr ago. We note that the SN dust retains directional information to within $1^{\circ}$ through its arrival in the inner Solar System, so that SN debris deposition on inert bodies such as the Moon will be anisotropic, and thus could in principle be used to infer directional information. In particular, we predict that existing lunar samples should show measurable $^{60}$Fe differences.Fry, Brian JFields, Brian DEllis, John RWed, 06 Apr 2016 05:52:48 GMT04 Apr 2016arXiv:1604.00958http://cds.cern.ch/record/2143998['arXiv:1604.00958']arXiv:1604.00958Prospects for Future Collider Physics
http://cds.cern.ch/record/2143438
One item on the agenda of future colliders is certain to be the Higgs boson. What is it trying to tell us? The primary objective of any future collider must surely be to identify physics beyond the Standard Model, and supersymmetry is one of the most studied options. it Is supersymmetry waiting for us and, if so, can LHC Run 2 find it? The big surprise from the initial 13-TeV LHC data has been the appearance of a possible signal for a new boson X with a mass ~750 GeV. What are the prospects for future colliders if the X(750) exists? One of the most intriguing possibilities in electroweak physics would be the discovery of non-perturbative phenomena. What are the prospects for observing sphalerons at the LHC or a future collider?Ellis, JohnMon, 04 Apr 2016 06:33:36 GMT01 Apr 2016arXiv:1604.00333http://cds.cern.ch/record/2143438['arXiv:1604.00333']arXiv:1604.00333On the MSSM Higgsino mass and fine tuning
http://cds.cern.ch/record/2143038
It is often argued that low fine tuning in the MSSM necessarily requires a rather light Higgsino. In this note we show that this need not be the case when a more complete set of soft SUSY breaking mass terms are included. In particular an Higgsino mass term, that correlates the $\mu-$term contribution with the soft SUSY-breaking Higgsino masses, significantly reduces the fine tuning even for Higgsinos in the TeV mass range where its relic abundance means it can make up all the dark matter.Ross, Graham GSchmidt-Hoberg, KaiStaub, FlorianFri, 01 Apr 2016 06:23:38 GMT30 Mar 2016arXiv:1603.09347http://cds.cern.ch/record/2143038['arXiv:1603.09347']arXiv:1603.09347The first observations of wide-band interferometers and the spectra of relic gravitons
http://cds.cern.ch/record/2142906
Stochastic backgrounds of relic gravitons of cosmological origin extend from frequencies of the order of the aHz up to the GHz range. Since the temperature and polarization anisotropies constrain the low frequency normalization of the spectra, in the concordance paradigm the strain amplitude corresponding to the frequency window of wide-band interferometers turns out to be, approximately, nine orders of magnitude smaller than the astounding signal recently reported and attributed to a binary black hole merger. The backgrounds of relic gravitons expected from the early Universe are compared with the stochastic foregrounds stemming from the estimated multiplicity of the astrophysical sources. It is suggested that while the astrophysical foregrounds are likely to dominate between few Hz and 10 kHz, relic gravitons with frequencies exceeding 100 kHz represent a potentially uncontaminated signal for the next generation of high-frequency detectors currently under scrutiny.Giovannini, MassimoFri, 01 Apr 2016 06:16:01 GMT30 Mar 2016arXiv:1603.09217http://cds.cern.ch/record/2142906['arXiv:1603.09217']arXiv:1603.09217Pinning down electroweak dipole operators of the top quark
http://cds.cern.ch/record/2142593
We consider hadronic top quark pair production and pair production in association with a photon or a $Z$ boson to probe electroweak dipole couplings in $t\bar{b}W$, $t\bar{t}\gamma$ and $t\bar{t}Z$ interactions. We demonstrate how measurements of these processes at the 13 TeV LHC can be combined to disentangle and constrain anomalous dipole operators. The construction of cross section ratios allows us to significantly reduce various uncertainties and exploit orthogonal sensitivity between the $t\bar{t}\gamma$ and $t\bar{t}Z$ couplings. In addition, we show that angular correlations in $t\bar{t}$ production can be used to constrain the remaining $t\bar{b}W$ dipole operator. Our approach yields excellent sensitivity to the anomalous couplings and can be a further step towards precise and direct measurements of the top quark electroweak interactions.Schulze, MarkusSoreq, YotamWed, 30 Mar 2016 06:09:38 GMT29 Mar 2016arXiv:1603.08911http://cds.cern.ch/record/2142593['arXiv:1603.08911']arXiv:1603.08911A 750 GeV graviton from holographic composite dark sectors
http://cds.cern.ch/record/2142579
We show that the 750 GeV di-photon excess can be interpreted as a spin-2 resonance arising from a strongly interacting dark sector featuring some departure from conformality. This spin-2 resonance has negligible couplings to the SM particles, with the exception of the SM gauge bosons which mediate the two sectors. We have explicitly studied the collider constraints as well as some theoretical bounds in a holographic five dimensional model with a warp factor that deviates from AdS$_5$. In particular, we have shown that it is not possible to decouple the vector resonances arising from the strong sector while explaining the di-photon anomaly and keeping the five dimensional gravity theory under perturbative control. However, due to the deformation of conformality, vector resonances with masses around the TeV scale can be present while all experimental constraints are met.Carmona, AdrianWed, 30 Mar 2016 06:08:47 GMT29 Mar 2016arXiv:1603.08913http://cds.cern.ch/record/2142579['arXiv:1603.08913']arXiv:1603.08913Demystifying the twistor construction of composite operators in N=4 super-Yang-Mills theory
http://cds.cern.ch/record/2142209
We explain some details of the construction of composite operators in N=4 SYM that we have elaborated earlier in the context of Lorentz harmonic chiral (LHC) superspace. We give a step-by-step elementary derivation and show that the result coincides with the recent hypothesis put forward in arXiv:1603.04471 within the twistor approach. We provide the appropriate LHC-to-twistors dictionary.Chicherin, DmitrySokatchev, EmeryTue, 29 Mar 2016 06:15:43 GMT28 Mar 2016arXiv:1603.08478http://cds.cern.ch/record/2142209['arXiv:1603.08478']arXiv:1603.08478Flavor hierarchies from dynamical scales
http://cds.cern.ch/record/2141285
One main obstacle for any beyond the SM (BSM) scenario solving the hierarchy problem is its potentially large contributions to electric dipole moments. An elegant way to avoid this problem is to have the light SM fermions couple to the BSM sector only through bilinears, $\bar ff$. This possibility can be neatly implemented in composite Higgs models. We study the implications of dynamically generating the fermion Yukawa couplings at different scales, relating larger scales to lighter SM fermions. We show that all flavor and CP-violating constraints can be easily accommodated for a BSM scale of few TeV, without requiring any extra symmetry. Contributions to B physics are mainly mediated by the top, giving a predictive pattern of deviations in $\Delta F=2$ and $\Delta F=1$ flavor observables that could be seen in future experiments.Panico, GiulianoPomarol, AlexThu, 24 Mar 2016 07:26:15 GMT21 Mar 2016arXiv:1603.06609http://cds.cern.ch/record/2141285['arXiv:1603.06609']arXiv:1603.06609Search for Sphalerons: IceCube vs. LHC
http://cds.cern.ch/record/2141265
We discuss the observability of neutrino-induced sphaleron transitions in the IceCube detector, encouraged by a recent paper by Tye and Wong (TW), which argued on the basis of a Bloch wave function in the periodic sphaleron potential that such transitions should be enhanced compared to most previous calculations. We calculate the dependence on neutrino energy of the sphaleron transition rate, comparing it to that for conventional neutrino interactions, and we discuss the observability of tau and multi-muon production in sphaleron-induced transitions. We use IceCube 4-year data to constrain the sphaleron rate, finding that it is comparable to the upper limit inferred previously from a recast of an ATLAS search for microscopic black holes at the LHC with $\sim 3$/fb of collisions at 13 TeV. The IceCube constraint is stronger for a sphaleron barrier height $E_{\rm Sph} \gtrsim 9$ TeV, and would be comparable with the prospective LHC sensitivity with 300/fb of data at 14 TeV if $E_{\rm Sph} \sim 11$ TeV.Ellis, JohnSakurai, KazukiSpannowsky, MichaelThu, 24 Mar 2016 07:21:17 GMT21 Mar 2016arXiv:1603.06573http://cds.cern.ch/record/2141265['arXiv:1603.06573']arXiv:1603.06573The double copy: Bremsstrahlung and accelerating black holes
http://cds.cern.ch/record/2140401
Advances in our understanding of perturbation theory suggest the existence of a correspondence between classical general relativity and Yang-Mills theory. A concrete example of this correspondence, which is known as the double copy, was recently introduced for the case of stationary Kerr-Schild spacetimes. Building on this foundation, we examine the simple time-dependent case of an accelerating, radiating point source. The gravitational solution, which generalises the Schwarzschild solution, includes a non-trivial stress-energy tensor. This stress-energy tensor corresponds to a gauge theoretic current in the double copy. We interpret both of these sources as representing the radiative part of the field. Furthermore, in the simple example of Bremsstrahlung, we determine a scattering amplitude describing the radiation, maintaining the double copy throughout. Our results provide the strongest evidence yet that the classical double copy is directly related to the BCJ double copy for scattering amplitudes.Luna, AndresMonteiro, RicardoNicholson, IsobelO'Connell, DonalWhite, Chris DMon, 21 Mar 2016 06:27:47 GMT17 Mar 2016arXiv:1603.05737http://cds.cern.ch/record/2140401['arXiv:1603.05737']arXiv:1603.05737Tutorial to SARAH
http://cds.cern.ch/record/2140397
I give in this brief tutorial a short practical introduction to the Mathematica package SARAH. First, it is shown how an existing model file can be changed to implement a new model in SARAH. In the second part, masses, vertices and renormalisation group equations are calculated with SARAH. Finally, the main commands to generate model files and output for other tools are summarised.Staub, FlorianMon, 21 Mar 2016 06:27:29 GMT18 Mar 2016arXiv:1603.05958http://cds.cern.ch/record/2140397['arXiv:1603.05958']arXiv:1603.05958A closer look at non-decoupling D-Terms
http://cds.cern.ch/record/2140390
Non-Decoupling D-Terms are an attractive possibility to enhance the tree-level mass of the standard model like Higgs boson in supersymmetric models. We discuss here for the case of a new Abelian gauge group two effects usually neglected in literature: (i) the size of the additional radiative corrections to the Higgs mass due to the presence of the new gauge coupling, and (ii) the impact of gauge kinetic mixing. It is shown that both effects reduce to some extent the positive effect of the non-decoupling D-terms on the Higgs mass.Staub, FlorianMon, 21 Mar 2016 06:27:26 GMT18 Mar 2016arXiv:1603.05852http://cds.cern.ch/record/2140390['arXiv:1603.05852']arXiv:1603.05852The string-junction picture of multiquark states: an update
http://cds.cern.ch/record/2140388
We recall and update, both theoretically and phenomenologically, our (nearly) forty-years-old proposal of a string-junction as a necessary complement to the conventional classification of hadrons based just on their quark-antiquark constituents. In that proposal single (though in general metastable) hadronic states are associated with "irreducible" gauge-invariant operators consisting of Wilson lines (visualized as strings of color flux tubes) that may either end on a quark or an antiquark, or annihilate in triplets at a junction $J$ or an anti-junction $\bar{J}$. For the junction-free sector (ordinary $q\, \bar{q}$ mesons and glueballs) the picture is supported by large-$N$ (number of colors) considerations as well as by a lattice strong-coupling expansion. Both imply the famous OZI rule suppressing quark-antiquark annihilation diagrams. For hadrons with $J$ and/or $\bar{J}$ constituents the same expansions support our proposal, including its generalization of the OZI rule to the suppression of $J-\bar{J}$ annihilation diagrams. Such a rule implies that hadrons with junctions are "mesophobic" and thus unusually narrow if they are below threshold for decaying into as many baryons as their total number of junctions (two for a tetraquark, three for a pentaquark). Experimental support for our claim, based on the observation that narrow multiquark states typically lie below (well above) the relevant baryonic (mesonic) thresholds, will be presented.Rossi, GiancarloVeneziano, GabrieleMon, 21 Mar 2016 06:27:26 GMT18 Mar 2016arXiv:1603.05830http://cds.cern.ch/record/2140388['arXiv:1603.05830']arXiv:1603.05830Relativistic causality and position space renormalization
http://cds.cern.ch/record/2139840
We survey the causal position space renormalization with a special attention to the role of Raymond Stora in the development of the subject. Renormalization is effected by subtracting pole terms in analytically regularized amplitudes. Residues are identified with periods whose relation to recent development in number theory is emphasized. We demonstrate the possibility of integration over internal vertices in the case of a (massless) conformal theory and display the dilation and the conformal anomaly.Todorov, IvanThu, 17 Mar 2016 11:37:41 GMT17 Mar 2016CERN-TH-2016-058http://cds.cern.ch/record/21398402016058Precision Islands in the Ising and $O(N)$ Models
http://cds.cern.ch/record/2139487
We make precise determinations of the leading scaling dimensions and operator product expansion (OPE) coefficients in the 3d Ising, $O(2)$, and $O(3)$ models from the conformal bootstrap with mixed correlators. We improve on previous studies by scanning over possible relative values of the leading OPE coefficients, which incorporates the physical information that there is only a single operator at a given scaling dimension. The scaling dimensions and OPE coefficients obtained for the 3d Ising model, $(\Delta_{\sigma}, \Delta_{\epsilon},\lambda_{\sigma\sigma\epsilon}, \lambda_{\epsilon\epsilon\epsilon}) = (0.5181489(10), 1.412625(10), 1.0518537(41), 1.532435(19))$, give the most precise determinations of these quantities to date.Kos, FilipPoland, DavidSimmons-Duffin, DavidVichi, AlessandroWed, 16 Mar 2016 07:27:32 GMT14 Mar 2016arXiv:1603.04436http://cds.cern.ch/record/2139487['arXiv:1603.04436']arXiv:1603.04436Top quark mass determination from the energy peaks of b-jets and B-hadrons at NLO QCD
http://cds.cern.ch/record/2138759
We analyze the energy spectra of $single$ b-jets and B-hadrons resulting from the production and decay of top quarks within the SM at the LHC at the NLO QCD. For both hadrons and jets, we calculate the correlation of the peak of the spectrum with the top quark mass, considering the "energy-peak" as an observable to determine the top quark mass. Such a method is motivated by our previous work where we argued that this approach can have reduced sensitivity to the details of the production mechanism of the top quark, whether it is higher-order QCD effects or new physics contributions. As part of the NLO improvement over the original proposal, we assess the residual sensitivity of the extracted top quark mass to perturbative effects both in top quark production and decay. For a 1% jet energy scale uncertainty (and assuming negligible statistical error), the top quark mass can then be extracted using the energy-peak of b-jets with an error +- (1.2 (exp) + 0.6(th)) GeV. We note that recently the CMS collaboration reported a top quark mass measurement based on the original proposal (with b-jets) so that our result contributes to a precise evaluation of the associated theory uncertainty. In view of the dominant jet energy scale uncertainty in the measurement using b-jets, we also investigate the extraction of the top quark mass from the energy-peak of the corresponding B-hadrons which, in principle, can be measured without this uncertainty. The calculation of the B-hadron energy spectrum is carried out using fragmentation functions at NLO. The dependence on the fragmentation scale turns out to be the largest theoretical uncertainty in this extraction of top quark mass. Future improvement of the treatment of bottom quark hadronization can reduce this uncertainty, rendering methods based on the B-hadron energy-peak competitive for the top quark mass measurement.Agashe, KaustubhKim, DoojinFranceschini, RobertoSchulze, MarkusMon, 14 Mar 2016 06:36:35 GMT10 Mar 2016arXiv:1603.03445http://cds.cern.ch/record/2138759['arXiv:1603.03445']arXiv:1603.03445