In recent years, the LHCb collaboration has claimed diverse deviations of their observations of generally \(B\)-meson decays from the Standard Model predictions. Influenza A virus subtype H5N1 novel newspaper was released yesterday, summarizing the province of affairs later Moriond 2017:
Status of the \(B\to K^*\mu^+\mu^−\) anomaly later Moriond 2017Wolfgang Altmannshofer, Christoph Niehoff, Peter Stangl, David M. Straub (the German linguistic communication language is then effective alongside these one-syllable surnames, isn't it?) in addition to Matthias Rindfleischetikettierungsüberwachungsaufgabenübertragungsgesetz convey looked at the tension alongside the newest data.
The Good-lookers, Matterhorn (1975): In the morning, they started their journeying at CERN (or inward Bern). I've made the would-be witty replacement of Bern alongside CERN then many times that I am non capable of singing this poesy reliably correctly anymore!
The novel information include the angular distribution of the decay mentioned inward the title, every bit measured past times the major (ATLAS in addition to CMS) detectors.
Microscopically, at the degree of quarks in addition to leptons, these decays of the \(B\)-mesons stand upwardly for to the\[
b\to sec + \mu^+ + \mu^-
\] transformation of the bottom-quark.
There seems to last a divergence from the Standard Model. But they run across that the divergence doesn't seem to visibly depend on \(q^2\) in addition to it's independent of the helicities, too. The begin fact encourages them to explicate the "extra processes" past times an extra four-fermion interaction including the fermions \(b,s,\mu,\mu\). There are diverse tensor structures that allow you lot to contract the iv spinors inward the four-fermion interactions in addition to i time they await carefully, the divergence from the Standard Model seems to last maximally hiding inward the novel physics (NP) term inward the Hamiltonian:\[
\eq{
\HH_{\rm eff} &= -\frac{4 G_F}{\sqrt{2}} V_{tb} V^*_{ts} \frac{e^2}{16\pi^2} \cdot C_9 O_9 + {\rm h.c.},\\
O_9 &= (\bar sec \gamma_\mu P_L b) (\bar \ell \gamma^\mu \ell)
}
\] There are numerous other possible damage a priori, upwardly to \(O_{10}\). Also, analogous operators may convey primes in addition to the prime number indicates the replacement of \(P_L\) alongside \(P_R\).
If you lot memorize this vocal close quarks, you lot should empathize all the four-fermion interactions unless you lot volition conclude that the vocal is close cheese, every bit one of the singers did. The ladies from the daughter band – those on the first photograph e'er posted on the web – are planning a comeback in addition to await for donations.
At whatever rate, solely the testify inward favor of a nonzero coefficient \(O_9\) from novel physics seems potent plenty to deserve the newspaper – in addition to the TRF spider web log postal service – in addition to the best stand upwardly for value of \(C_9\) seems to last negative and\[
C_9 = -1.21 \pm 0.22
\] which agency that the experimental information hollo for that \(C_9\) is nonzero (it should last null inward the Standard Model) at the 4.9-sigma level. Not bad. Well, in that location is also a similar precisely weaker anomaly for \(C_{10}\) that multiplies a similar operator alongside an extra \(\gamma_5\) in addition to whose best stand upwardly for is:\[
\eq{
O_{10} &= (\bar sec \gamma_\mu P_L b) (\bar \ell \gamma^\mu \gamma_5 \ell)\\
C_{10} &= +0.69\pm 0.25
}
\] which differs from the Standard Model's null past times 2.9 sigma. The numbers larn far clear that the hypothesis that \(C_{9}=-C_{10}\) is rather compatible alongside the data, too, inside i sigma, in addition to the best stand upwardly for for this \(C_{9}=-C_{10}\) is \(-0.62\pm 0.14\) or so, a 4.2-sigma divergence from null (I believe that \(-0.62\pm 0.14\) should actually last multiplied past times \(\sqrt{2}\) precisely allow me non brand this confusion likewise visible).
The German/Ohio authors interpret this upshot to diverse other parameterizations of the LFUs (lepton flavour universality parameters) in addition to if I empathize the ultimate claim well, they basically state that similar anomalies from ATLAS+CMS, LHCb, and Belle seem to last consistent alongside each other in addition to alongside the extra novel physics term that was proposed above.
Some skeptics could state that these anomalies could last due to some hard QCD effects. But the bottom-quark is pretty heavy in addition to thus "ignoring" the gluy, mucilaginous surroundings around itself then I tend to remember that the divergence from the Standard Model is rather exciting.
I've made fun of the German linguistic communication language then I desire to brand certain that the the United States readers don't remember that they're untouchable. ;-)
If it exists, the authors say, the clear deviations from the Standard Model could last made really potent past times the experiments really soon.
Theoretically, I would endeavor to explicate this four-fermion interaction past times the telephone commutation of a novel guess boson or a scalar particle precisely I am non capable of giving you lot a to a greater extent than refined allow lone stringy inspired detailed story close this novel upshot at this moment.