Dr Vempati has made outstanding contributions, with the common theme of
Flavour violation, which span a wide range of Particle Physics from supersymmetry to
extra dimensions and from the Higgs boson to neutrino physics. His leadership qualities
in developing a supersymmetric spectrum generator is highly commendable.
Thesis and Guide details:
Details of CSIR Fellowship/ Associateship held, if any or from other sources/ agencies.
Significant foreign assignments:
(a) Significant contributions to science and/ or technology development by the nominee
based on the work done in India during most part of last 5 years:
The nominee’s scientific research contributions are mainly in the area of
physics Beyond the Standard Model, which tries to embed the Standard
Model of particle Physics, in to a much larger theoretical structure. The
purpose of this larger theoretical structure is mainly to provide
explanations of various anomalies that plague the Standard Model
like neutrino masses, dark matter, etc. Two most popular theoretical
structures are (a) supersymmetry and (b) extra dimensions. The
nominee’s work has focused on (i) building tools that improve the
testablility of supersymmetric models and their a generalizations,
(ii) studying the implications of the interplay between astro-particle
physics and supersymmetric models and finding new connections between
apparently unrelated areas like flavor physics and dark matter and (iii)
elucidating various aspects of flavor physics constraints on Randall-
Sundrum Models and pointing out connections between two extra
dimensional models namely, the Arkani-hamed, Dvali, Dimopoulos (ADD)
models and Randall Sundrum (RS) Models. Details of the nominee’s work
are given below.
(i) New Directions: Flavoured Scatterings in Early Universe
Most of the flavour violation observed in the laboratories is through
decay processes. The early universe provides an interesting system
where flavour violation in scattering processes can play an important
role. This is particularly true in supersymmetric models that have a natural
dark matter candidate in terms of the lightest supersymmetric particle.
The relic density of the dark-matter candidate depends on the
scattering cross-section with various other particles at the decoupling time.
The nominee has demonstrated that Flavor violation if present in
the soft sector plays an important role in modifying the scattering
cross-section. The nominee has presented this idea to the
case of slepton co-annihilations and has shown that flavour violating
scatterings with slepton initial states or mediators can be dominant
compared to their flavour conserving counter-parts. This has
since been applied to the hadronic sector and different supersymmetric
models by various groups. The amount of flavour violation can be arranged
to be large by moving to a parameter space where low energy
experimental constraints are suppressed, leading to regions that
have been dubbed `flavoured co-annihilations'.
Accurate supersymmetric mass spectra, in various models of supersymmetric
Breaking, is the need of the hour especially in the light of LHC data.
Computation of the supersymmetric mass spectrum at high precision is a
difficult task, which involves several coupled non-linear differential equations,
matrix diagonalisations, loop functions, stability analysis, minimization, and
iterative techniques, etc. This is typically done by huge computer programs
called spectrum generators. The presently available spectrum generators
however, are not suitable to handle flavour violation or non-zero neutrino
masses through the seesaw mechanisms. Therefore, it is important to have
such a code to deal with the current data from LHC, flavour physics, or
dark matter. For example, a tiny amount of flavour violation present in the
squark sector can completely remove the `strong' constraints on many
supersymmetric models from the rare decay of b-quark to s-quark + photon.
And more importantly, realistic models of supersymmetry breaking do
predict some flavour violation in the soft terms.
(b) Impact of the contributions in the field concerned:
The work of the Nominees has received wide attention. The impact can be
summarized In terms of the citation record of the Nominee. According to
inSPIRE HEP database, the total number of citations of the Nominee
(including published and unpublished ) is 2261 and only published in journals
is 1533. His average citations per paper is 40.33, h index is 20, when
considering only published work. According to Google Scholar, his total
number of citations is 1854 (excluding linear collider Reports), h-index is 20,
i10 index Is 30.
Places where work of last 5 years has been referred/ cited in Books, Reviews:
Names of the industries in which the technology (ies) has (have) been used :
The achievements already been recognised by Awards by any learned body:
The Awardee a fellow of the Indian National Science Academy/Indian Academy of Sciences/National
Academy of Sciences/Others:
The Awardee delivered invited lecture(s) in India/abroad and/or chaired any scientific
Internatiional Conference Symposium:
List of Awardee's 10 most significant publications.
List of Awardee's 5 most significant publications during the last 5 years
List of Awardee's 5 most significant publications from out of work done in India
during the last five years:
Complete list of publications in standard refereed journals:
Complete list of publications with foreign collaborators (indicating your status
List of papers published in Conferences /Symposia/ Seminars, etc:
List of the most outstanding Technical Reports/ Review Articles:
Statement regarding collaboration with scientists abroad:
Total number of patents granted in last five years.
Details of Books published: