Figure of the month September 2013
News: PhD graduate of the IFM-UMSNH was granted with a scholarship to study at Harvard University

Dr. Arturo Avelino Huerta, PhD graduate of the Instituto de Física y Matemáticas of the Universidad Michoacana has got one of the firsts scholarships offered from the Fundación México in Harvard and CONACYT to work with Dr. Robert P. Kirshner's group at Harvard University. Dr. Robert P. Kirshner is the Clowes Professor of Science at Harvard and one of the leading scientists around the world working on the measurement of the accelerated expansion of the universe by using Supernovae. Dr. Avelino's work will consist on minimizing the systematic uncertainties of the distances to distant Supernovae estimated from near-infrared observations. The measurement of the distances to these objects are an important issue for the study of the expansion of the universe . However, data is still subject to several uncertainties. At the IFM-UMSNH, Dr. Avelino worked under the direction of Dr. Ulises Nucamendi with cosmological models to explain the accelerated expansion of the Universe. The students and members of the IFM congratulate Dr. Avelino Huerta for this accomplishment and whish him success in his stay.

News: PhD student of the IFM-UMSNH got one of the Robert Snyder student travel awards

The PhD student Waleed Abuhani of the IFM-UMSNH has received the Robert Snyder travel award at the 62nd Denver X-ray Conference due to his work: Characterizing Fundamental Parameters based analysis for soil-ceramic matrices in polarized Energy Dispersive X-ray Fluorescence Spectrometry (pEDXRF). This work was performed under the direction of Dr. Nabanita Dasgupta-Schubert and Dr. Luis Villaseñor with the pEDXRF equipment located at the radiation laboratory of the university (IFM-UMSNH). The International Denver Xray Conference is one of the biggest and most important conferences on X ray analysis. The Robert Snyder student travel awards are given to 3 students with outstanding contributions in the field of Xray Flourescence and 3 in the field of Xray Diffraction. This is an important recognition for Abuhani's work and the radiation laboratory.

Figure of the month July 2013
Figura del mes

Carbon nano-tubes are tubular 3D graphene structures with nm diameters and μm-mm lengths. They possess unique electrical, mechanical and thermal properties that are revolutionizing studies in areas such as condensed matter physics, electronics, materials chemistry, biology and medicine. In experiments conducted at the Radiation Lab (IFM) and the Phytotechnology Lab (IIQB) of the UMSNH ( DK Tiwari et al, Appl. Nanosc. (2013) DOI: 10.1007/s13204-013-0236-7 ), the interaction of CNTs with plant cells has demonstrated that low-dose multi-walled CNTs (MWCNTs) can dramatically improve the growth of maize seedlings and improve their mineral nutrient content. The mechanism is thought to be through the enhanced capacity of CNTs to deliver water to the growing cells by direct penetration. Figures on the left and on the rigth show SEM images of the seed-coat of the seedling near the emerging root without (Control) and with the MWCNT application respectively where the perforations caused by the MWCNT are clearly visible. While further research is needed, in the future CNT aided agriculture - "nanoagriculture" - might provide a viable alternative to transgenic food-crops.

Figure of the month May 2013
Figura del mes

Recent results of the KASCADE-Grande cosmic ray observatory provided evidence for an ankle-like feature in the spectrum for light elements (green curve), namely a hardening at E = 10**17 eV. The recovery in the spectrum of light cosmic rays could be the first indication of an injection spectrum from a new (extragalactic) source population of high energy cosmic rays. Therefore, this could be the first experimental evidence in favor of the long-sought cosmic ray galactic-extragalactic transition. The last year, the KASCADE-Grande experiment provided also evidence for a new knee-like structure in the all-particle spectrum of cosmic rays (black curve) at E = 10**16.92 eV, which was found to be due to a steepening in the flux of heavy primary particles (blue curve), called the iron-knee. The results about the ankle-light feature were published in Phys. Rev. D 87, 081101(R) (2013) by the KASCADE-Grande Collaboration, in which Dr. J.C. Arteaga-Velázquez , member of the IFM-UMSNH, is actively participating.

Outstanding result of January 2013
Figure of the month

Black holes traveling at supersonic on a sea of gas produce a shock cone, like the wake behind a ship on the sea. That shock cone is interesting because it vibrates and may explain some of the high energy observations related to Quasi Periodic Oscillations (QPOs). It was recently shown that when the black hole rotates, the cone oscillates and gets destroyed. Our numerical relativity group recently discovered through numerical simulations, that when using advanced numerical methods that allow the gas to truly enter the rotating black hole (not as previously reported by other groups), the shock cone is stable. In the figure the density of the shock cone and its motion is shown for a wind moving at Mach 5. The results were recently published in the Monthly Notices of the Royal Astronomical Society, 426 (2012) 732-738, by our students Alejandro Cruz Osorio and Fabio D. Lora Clavijo, and Dr. Francisco Siddhartha Guzman, members of the Numerical Relativity Group at the IFM.

Outstanding result of February 2012
Figure of the month

KASCADE-Grande is an air-shower observatory devoted to the detection of cosmic rays with energies in the range of $10^{16}$ and $10^{18}$ eV. This energy region is of particular interest for the cosmic ray astrophysics, since it is the place where several models predict the existence of a galactic- extragalactic transition in the cosmic ray spectrum and the presence of a break in the flux of its heavy component. The detection of these features requires detailed and simultaneous measurements of the energy and composition of cosmic rays with sufficient statistics. This kind of studies are possible for the first time in KASCADE-Grande due to the accurate measurements of several air-shower observables, i.e., the number of charged particle, electrons and muons in the shower, using the different detector systems of the observatory.
By classifying the detected air showers into electron-poor and electron- rich events on the basis of the charged over muon number ratio, the corresponding energy spectra of the light (electron-rich) and heavy (electron-poor) components of cosmic rays in the interval $10^{16}- 10^{18}$ eV were obtained (see figure). It was discovered that the energy spectrum of the heavy component shows a knee-like structure around 90 PeV. This feature is responsible for a steepening recently observed by the KASCADE-Grande experiment in the all-particle energy spectrum.
Dr. J.C. Arteaga-Velazquez, researcher of the IFM, worked on the development of one of these techniques to reconstruct the light and heavy spectra of cosmic rays. Results were published in PRL 107, 171104 (2011) . arXiv:1107.5885v2 [astro-ph].

Outstanding result of October 2011

 One of the outstanding problems in theoretical particle physics is the qualitative and quantitative understanding of the phenomenon of confinement: the fact that quarks or any other colored combination of elementary particles can never be observed as isolated physical states. One of the main directions of research followed over the last decade is the application of the variational principle to Yang-Mills theories in Coulomb gauge (with static color charges) which, upon using a Gaussian ansatz for the vacuum functional of the theory, yields a set of equations of Dyson-Schwinger type. However, including the potential between static color charges (approximated by the so-called color Coulomb potential) leads to inconsistencies. Very recently, we have adapted a functional renormalization group of Wilsonian type to this Hamiltonian formulation. The corresponding flow equations can be solved consistently, in particular, the so-called Coulomb form factor shows a power behavior in the infrared presented in the double-logarithmic plot (for momenta above the infrared cutoff k_{min} introduced for technical reasons). Together with the numerical result for the ghost correlator, one obtains a potential that varies in momentum space like p^{-3.85} in the limit of small momenta, quite close to the expected p^{-4} which corresponds to a potential that rises linearly with the distance between the color charges, see M. Leder, H. Reinhardt, A. Weber, and J.M. Pawlowski, preprint arXiv:1105.0800 [hep-th].

Outstanding result of February 2010

 This figure shows this equal-mass head-on collision of two virialized balls of self-gravitating Bose Condensate (BEC) described by the Gross-Pitaevskii equation (mean field description of a BEC at T=0). BECs are considered to be a dark matter candidate. This figure in fact represents the collision of two BEC dark matter halos (either galactic or cluster size). Notice the pattern of interference that soon will be shown to provide predictions that support or rule out the BEC as dark matter. (Left) the gravitational potential along the head-on axis, (middle) the density of probability along the head-on axis and (right) 2d flavor of the density of probability. Notice the solitonic-like behavior of the two blobs. This result was published in Phys.Rev.D83:103513,2011 , and is avalable also at arXiv:1105.2066v1 [astro-ph.CO].

Outstanding result of February 2010

 In the period 1960-1963 and in a series of works published in the most prestigious mathematics international journal, called Annals of Mathematics, Prof. Kunihiko Kodaira gave a classification of smooth projective surfaces over the field of complex numbers. Later on, in the period 1969-1977, David Mumford and Enrico Bombieri extended this classification to smooth projective surfaces over any algebraically closed field of any arbitrary characteristic. Special interest has been given to understand the geometry of the case of smooth projective rational surfaces over a fixed algebraically closed field (such interest owes its origin to the italian school of Algebraic Geometry of the nineteen and the begining of the twentieth centuries such as Castelnuovo, Chisini, Del Pezzo, Enriques and Severi to cite a few). Significant results have been obtained by Prof. Brian Harbourne from the University of Nebraska-Lincoln (USA) between 1985 and 2009, also in the period 2002-2009 by the members of the research group, calles Singacom, of the University of Valladolid (Spain) and whose coordinator is Prof. Antonio Campillo. Recently, between 2007 and 2010, the members of the group, called Algebraic Geometry Team, of the University of Michoacan and whose coordinator is Prof. Mustapha Lahyane have obtained significant results about the Geometry of new classes of smooth projective rational surfaces over an algebraically closed field of any characteristic. The results are based on two new concepts: the first is numerical and the second is a generalization of the so called Enriques diagrams (Enriques diagrams have been used intensively by the members of the Singacom group, by the Barcelona group whose coordinator is Prof. Eduardo Casas-Alvero and by Prof. Gerard Gonzalez-Sprinberg from the University of Grenoble (France)) . The picture shows a new family of smooth projective rational surfaces whose all geometries, except the two irreducible and reduced curves (the two green ones in the picture), are encoded in a well-defined divisor associated to the surface. This amazing result constitutes a particular case of many results obtained by Prof. Mustapha Lahyane (IFM-UMSNH) and which are published in the volume 214 (issue 7, July 2010, pages 1217-1248) of the Jorunal of Pure and Applied Algebra.

Outstanding result of the month (October 2009)

 Life time of wormholes can be extended if electric charge is added. In previous studies [Class. Quantum Grav. 26 (2009) 015010, Class. Quantum Grav. 26 (2009) 015011], González, Guzmán and Sarbach, members of the IFM showed that standard Wormholes supported by a ghost scalar field are unstable, both, based on the analysis of perturbations and in the non-linear regime using numerical relativity. They established that the time scale associated to the collapse into a black hole is of the order of the throat's areal radius divided by the speed of light, which is of the order of a few microseconds for a throat with areal radius of one kilometer. In their more recent paper [Phys. Rev. D 80, 024023 (2009)], our three members show that Wormhole solutions with electrictromagnetic charge are also unstable in the regime allowed for the study (a mixture of perturbation analysis and numerical methods), however the time scale for the collapse can be increased by a factor of 100 (!).

The book Beyond partial differential equations. On linear and quasi-linear abstract hyperbolic evolution equations by Professor Horst Beyer (IFM), published in the Lecture Notes on Mathematics #1898, has been included in the sixteen HIGHLIGHTS selected by the editors of Zentralblatt MATH for 2008. (see more).

Figura del Mes: Construimos una asintótica para tiempos grandes para todas las soluciones del sistema de Lamb no lineal, que tienen energía finita, y por primera vez se establece tal asint\'otica en la norma energética global para dichas soluciones. Es decir, cada solución a el sistema acoplado decae a una suma de dos componentes cuando $t\to+\infty$: un estado estacionario y una onda que se dispersó. Las ondas que se dispersan corresponden a estados asitóticos incidentes y reflejados. Finalmente se construyen los operadores de dispersión y se obtienen condiciones necesarias para los estados asintóticos. Estos resultados están reportados en el artículo {\sf Scattering in the Zero-mass Lamb System" } aceptado para su publicación en PHYSICS LETTERS A y cuyos autores son: Dr. Anatoli Merzon y M.C. Marco Antonio Taneco-Hernández.Para saber máa presiona aquí. (Para ver la figura con mejor calidad: hacer click en la figura).

Figura del Mes: La Colaboración Pierre Auger a la que pertenence el Instituto de Física y Matemáticas descubrió que las fuentes de los rayos cósmicos de la más alta energía no están distribuidas uniformemente en el cielo. Por el contrario, los resultados del Observatorio Pierre Auger vinculan a las fuentes de estas misteriosas partículas con galaxias cercanas caracterizadas por tener núcleos activos en su interior. Nuestros participantes en la colaboración Auger son Luis Manuel Villaseñor y Umberto Cotti . (Para ver la figura con mejor calidad: hacer click en la figura). Illustration Credit: Pierre Auger Observatory Team.