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Releases: flav-io/flavio

v0.17

21 Dec 14:06
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The main new feature in this release is the addition of the branching ratio of the inclusive semi-leptonic B decay B→Xclν, with l=e or μ (or their average). Many thanks to Paolo Gambino for useful discussions and for sharing numerical results necessary for implementing and validating this! See arXiv:1411.6560 and references therein for details on the theory.

An additional, minor improvement since v0.16.1 concerns the treatment of correlated ucertainties in Bayesian fits; see commit a32c80d for details.

Finally, the default values of masses and widths have been updated from PDG 2015 to PDG 2016 values. There has not been any numerically relevant change for the currently implemented observables.

v0.16.1

15 Dec 11:14
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This bug fix release fixes

  • a regression introduced by the recent internal change in the Constraints class in v0.16 that broke the fit functions,
  • an inconsistency in the combination of experimental likelihoods in the presence of multiple experiments measuring the same observable when using the FastFit class.

Additional unit tests have been added to improve the stability of these fitting functions.

v0.16

13 Dec 21:12
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This release focuses on stability improvements with only few new features.

Improvements on the physics side:

  • Added lepton flavour ratios for B->Plnu decays, e.g. <Rtaumu>(B0->Dlnu)
  • Added lepton flavour ratios for B->Xll decays, e.g. <Remu>(B->Xsll)
  • Added measurements of B->K*mumu "optimised" angular observables (P') by LHCb

Other improvements:

  • More consistent behaviour of flavio.plots.band_plot when using the pre_calculated_z and interpolation_factor options (see API docs)
  • flavio.plots.q2_plot_exp now properly handles asymmetric experimental uncertainties

In addition there have been a few under-the-hood changes in preparation for future features.

v0.15.1

18 Nov 08:21
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This minor release fixes the following bugs:

  • An erroneous factor of 1/2 in the angular observables AFB, FH, as well as the direct CP asymmetry in B->Pll decays was removed. Note that these quantities are compatible with zero in the SM, so this is relevant in the presence of new physics. Thanks to Christoph Niehoff for pointing this out.
  • The plot function q2_plot_th_bin now also works for non-SM Wilson coefficients (#24, thanks @f-thiele)

As a new feature, a function np_uncertainty was added that works just like sm_uncertainty but allows to specify non-SM Wilson coefficients. This allows to compute the uncertainties in the presence of new physics (see API docs).

v0.15

04 Nov 09:07
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The major new physics feature in this release is the addition of the branching ratio of the rare inclusive B→Xql+l- (l=e or μ) decay. Many thanks to Tobias Huber for providing analytical expressions and making numerical cross-checks that made the implementation of (most of) the corrections in arXiv:1503.04849 possible. Thanks also to the Munich Institute for Astro- and Particle Physics (MIAPP) for hospitality during this effort.

Another new feature is more cosmetic: metadata have been added to all observables, making it possible to split the list of observables into categories rather than one huge list.

Finally, thanks to Christoph Niehoff for improvements and cross-checks in Bq→l+l-.

v0.14.1

18 Oct 08:11
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This release does not bring any new features but various speed optimisations, most significantly:

  • Observables in B→Vll at very low q², that used to be slow to compute, are now a factor of 50 (fifty) faster! (318944e)
  • Generating random parameter sets is now 4 times faster, which also speeds up the generation of pseudo measurements for FastFit (0758c67)

v0.14

14 Oct 07:53
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News in this release:

  • New observable: effective lifetime in Bs→ll added. Thanks to @ChristophNiehoff for this addition!
  • Improvements in the plotting function flavio.plots.band_plot
    • It is now possible to save the data corresponding to any individual likelihood plot, which allows to easily change or rearrange plots later without having to recompute the likelihood. Thanks to Albert Puig for this addition!
    • It is now possible to interpolate the likelihood in between computed points to obtain smoother contours without computing on a finer grid. For the time being, this feature must be activated manually by setting interpolation_factor to an integer greater than 1.
  • Typos in measurements fixed and measurements of Λb→Λμμ added

v0.13.1

07 Oct 06:44
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This point release features a few minor improvements:

  • Two typos in measurements fixed (thanks to S. Reichert for spotting one of them)
  • Improvement in plot functions: band_plot now plots multiple confidence levels and supports legends out of the box
  • Stability improvements for FastFit

v0.13

28 Sep 07:50
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The focus in this release is on experimental measurements and treatment of likelihoods:

  • A large number of measurements by LHCb have been added - thanks to Stefanie Reichert for that!
  • While by default only the most recent measurements of an observable by a given experiment are included in the code, data files for older measurements can be found in a separate repository now.
  • A new function to read measurements from a URL can be useful for this purpose: for instance
flavio.measurements.read_url(
    'https://github.com/flav-io/measurements/blob/master/2011-lhcb-bksmumu.yaml')

All existing mesurements can be cleared with the new method flavio.Measurement.clear_all().

  • The combination of univariate likelihoods has been completely rewritten. For parameters or measurements with several uncertainties, these are now combined by computing the convolution of the PDFs. Here is an example for a symmetric and an asymmetric uncertainty. Thanks to Jens Jasche for discussions.
  • For measurements, instead of central values and uncertainties, now also upper limits can be specified. In the YAML data file, they are written simply as a string of the form < 1.5e-8 @95% CL - this works for arbitrary confidence levels.

Finally, there are two new observables: the direct CP asymmetries in B→K*ll and B→Kll.

v0.12

20 Sep 14:14
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This release adds observables in three more decays:

  • Branching ratios of D→lν and Ds→lν decays (where l=e or μ) that are used to measure the CKM elements Vcs and Vcd
  • Branching ratio and angular observables of Λb→Λll (where l=e or μ) that is based on the b→sll transition and is closely related to B→(K, K*)ll.

The Λb decay is based on the lattice form factors of arXiv:1602.01399 and the angular distribution derived in arXiv:1410.2115. Special thanks to Danny van Dyk for discussions.

On an unrelated note, there is now a repository with example Jupyter notebooks that will showcase some of the features in the future (and contributions are of course welcome).