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Investigation of spatial parity in reactions of polarized neutrons with light nuclei is an important topic in the framework of exploring the fundamental problem of understanding the manifestation of the weak interaction in nuclear reactions and for estimating the parameters of the weak nucleon–nucleon interaction. In this paper, the ongoing experimental program of highly sensitive and high-precision measurements of P‑odd asymmetries in the reactions of polarized thermal and cold neutrons with lithium and boron nuclei is reviewed. Within this program, the coefficients of P-odd asymmetry of reaction products in the reactions induced by cold- and thermal-neutrons on the isotopes of light nuclei 6Li and 10B were measured with record-high sensitivity ~10–8 as $$\alpha _{{P{\text{ - odd}}}}^{{^{{\text{6}}}{\text{Li}}{\text{,exp}}}} = - (8.8 \pm 2.1) \times {{10}^{{ - 8}}}$$ , $$\alpha _{{P{\text{ - odd}}}}^{{^{{10}}{\text{B}},\gamma ,\exp }} = (0.0 \pm {{2.6}_{{{\text{stat}}.}}} \pm {{1.1}_{{{\text{syst}}{\text{.}}}}}) \times {{10}^{{ - 8}}},$$ and $$\alpha _{{P{\text{ - odd}}}}^{{{{\alpha }_{0}} + {{\alpha }_{1}}{{,}^{{10}}}B,\exp }} = - (11.2 \pm 3.4) \times {{10}^{{ - 8}}}$$ . For the first time ever, nonzero values were obtained for two of these asymmetries. Our data for tritium emission in the $$^{6}{\text{Li(}}n,a{{)}^{3}}{\text{H}}$$ reaction and γ emission in the $$^{{10}}{\text{B}}{{(n,a)}^{{74}}}{\text{Li}}^{*} \to \gamma \to {{\,}^{7}}{\kern 1pt} {\text{Li(gr}}{\text{.st}}{\text{.)}}$$ reaction agree with those of other experiments when interpreted within the cluster model, but rule out the so-called “best DDH values” of weak-interaction coupling constants. Interpreting the data on these reactions relying on “first principles” only would be highly desirable.

The method of asymptotic normalization coefficients is a standard approach for studies of two-body non-resonant radiative capture processes in nuclear astrophysics. This method suggests a fully analytical description of the radiative capture cross section in the low-energy region of the astrophysical interest. We demonstrate how this method can be generalized to the case of three-body $2p$ radiative captures. It was found that an essential feature of this process is the highly correlated nature of the capture. This reflects the complexity of three-body Coulomb continuum problem. Radiative capture $^{15}$O+$p$+$p \rightarrow ^{\,17}$Ne+$\gamma$ is considered as an illustration., Comment: 9 pages, 8 figures

The soft dipole E1 strength function is calculated for the transition from the He60+ ground state to the 1- continuum He4+n+n. The calculations were performed within the hyperspherical harmonics formalism. The sensitivity of the results to the He6 ground-state structure and to final-state interactions, are analyzed. The large-basis calculations show the reliably converged results for soft dipole strength function and for momentum correlations of the He6→He4+n+n dissociation products. Transition mechanisms are analyzed based on the momentum correlations. The comparison with experimental data is provided.

We present measurements of P-odd asymmetry of emission of α-particles in the B10(n,α)Li7 nuclear reaction, which are carried out using beams of polarized cold neutrons at Petersburg Nuclear Physics Institute (PNPI, Gatchina, Russia) and Institut Max von Laue – Paul Langevin (ILL, Grenoble, France) nuclear reactors. The α-particle detector is an ionization chamber with insensitive gaseous layer. We measured the P-odd asymmetry coefficient to be equal to αP-oddB10,α=−(11.2±3.4)⋅10−8.

Coulomb and nuclear dissociation of $^{17}$Ne on light and heavy targets are studied theoretically. The dipole E1 strength function is determined in a broad energy range including energies of astrophysical interest. Dependence of the strength function on different parameters of the $^{17}$Ne ground state structure and continuum dynamics is analyzed in a three-body model. The discovered dependence plays an important role for studies of the strength functions for the three-body E1 dissociation and radiative capture. The constraints on the $[s^2]/[d^2]$ configuration mixing in $^{17}$Ne and on $p$-wave interaction in the $^{15}$O+$p$ channel are imposed based on experimental data for $^{17}$Ne Coulomb dissociation on heavy target., 12 pages, 13 figures

An unusually large value of the C22 matter radius, extracted by Tanaka et al. [Phys. Rev. Lett. 104, 062701 (2010)PRLTAO0031-900710.1103/PhysRevLett.104.062701] from measured reaction cross sections, attracted great attention of scientific community. Since that time, several experimental works related to the C22 nucleus have appeared in the literature. Some of the experimental data, measured with high accuracy, allow us to fix C22 structure more reliably. Two limiting models reproducing C22 nuclear structure within the three-body cluster approach, that allow us to describe all existing experimental data, are presented. The C22 ground state, continuum structure, and geometry are obtained. With fixed C22 wave function, the prediction for the soft dipole mode in C22, which is studied in the process of Coulomb fragmentation, is performed.

A new method to measure polarization of cold/thermal neutrons using P-even asymmetry in nuclear reactions induced by polarized neutrons is proposed. A scheme profiting from a large correlation of the neutron spin and the circular γ-quantum polarization in the reaction (n, γ) of polarized neutrons with nuclei is analyzed. This method could be used, for instance, to measure the neutron-beam polarization in experiments with frequently varying configuration. We show that high accuracy and reliability of measurements could be expected.

We present two experiments measuring the parity-violating asymmetry (P-odd) of tritons emission in the reaction 6Li(n,α)3H and γ-quanta emission in the reaction 10B(n,α)7Li* → 7Li + γ with polarized cold neutrons, aiming at estimation of the weak meson-nucleon coupling constants. These experiments started in the PNPI, Gatchina and continued in the ILL, Grenoble. We describe an integral method to measure P-odd asymmetry and the two experiments. The results of our measurements are: $\alpha{}_{P-odd}^{6Li}=(-8.8\pm2.1)\cdot10^{-8}$ and $\alpha{}_{P-odd}^{10B}=(0.8\pm3.9)\cdot10^{-8}$ .

We present results of measurement of the P-odd asymmetry αP-odd of γ-quanta emission in the nuclear reaction 10B(n,α)7Li*→γ+7Li(g.s.) with polarized cold neutrons. The experiment was carried out using a new version of the integral measuring method. The frequency of neutron spin-flip is higher in this method than the typical reactor power noise frequency; this condition decreases experimental uncertainties. The result is αP‐odd10B=+(0.8±3.9)×10-8; “zero” experiments are taken into account. Using this value, we constrain the weak neutral current constant in the framework of the cluster model to fπ10B≤2.4×10-7 (at 90% c.l.). This constraint does not contradict the estimation obtained from the nuclear reaction 6Li(n,α)3H: fπ6Li≤1.1×10-7 (at 90% c.l.). However, both these constraints contradict the “best” value of the Quark model by Desplanques, Donoughe, and Holstein fπDDH=4.6×10-7.

An analytical wave function for the 11Li ground state is constructed in a three-body 9Li + n + n approach. Its parameters are fixed from the fit to the set of most accurate experimental data and tested on all other available data. The obtained 11Li ground state wave function allows to describe all considered experimental data within their error bars simultaneously. The main contributions to the 11Li ground state wave function are found to come from (s1 / 2)2 (37%) and (p1 / 2)2 (47%) components.

Using the two-proton-halo candidate 17 Ne as an example, we discuss the possibility of a soft-dipole mode in protonrich nuclei. The study is based on a three-body model considering 17 Ne as an 15 O core and two protons. Our calculation predicts a relatively narrow peak in the E1 strength function which exhausts a considerable part of the E1 cluster sum rule at energies only a few MeV above the 2 p threshold. We also calculate the 2 p capture cross section on 15 O at astrophysical conditions appropriate for explosive hydrogen burning in novae and X-ray bursts. Our calculation includes consistently resonant and non-resonant contributions to the astrophysical capture rate. We find that for a broad range of temperatures (including temperatures in excess of 10 9 K) the rate is dominated by non-resonant contributions.

One-proton removal reactions of 936 MeV/u 8 B have been studied with carbon and lead as breakup targets. Using the FRS at GSI, the longitudinal momentum distributions of the 7 Be fragments and the one-proton removal cross section of 8 B were measured. The relative contributions of the breakup channels leading to 7 Be in its ground state and excited state at 429 keV ( 7 Be ∗ ) have been determined from measurements of γ rays in coincidence with the fragments from the one-proton removal reaction. The experimental breakup data are discussed in the context of a theoretical ( α+ 3 He + p ) three-body model. The combined data from the two targets allow a determination of the weight of the 7 Be ∗ component in the 8 B ground state wave function as (13.3±2.2%)

F. Wamers et al.; 4 pags.; 2 figs. Open Access funded by Creative Commons Atribution Licence 2.0, We have studied one-proton-removal reactions of about 500 MeV/u17Ne beams on a carbon target at the R3B/LAND setup at GSI by detecting beam-like 15Op and determining their relative-energy distribution. We exclusively selected the removal of a 17Ne halo proton, and the Glauber-model analysis of the 16F momentum distribution resulted in an s 2 contribution in the 17Ne ground state of about 40 %. C Owned by the authors, published by EDP Sciences, 2014, This work was supported by the Alliance Program of the Helmholtz Association (HA216/EMMI), by the German Federal Ministry for Education and Research (BMBF) (project 05P12RDFN8) by HIC for FAIR, by Eurons (European Commission contract no. 506065), and by GSI.

The interaction of 2 + mixed isospin states at 16.6, 16.9 MeV in 8 Be with α – α continuum is studied. Qualitative coupled channel model is used. Estimates, as well as results of the three-cluster calculations are used to put constraints on the model. Two methods to treat isospin mixing in the system are discussed.

The structure and spectrum of the three-cluster states in 8 Be around 16–20 MeV was studied in the framework of the hyperspherical harmonic method. For that purpose we have developed a potential formalism for T– p and 3 He – n (3+1) scattering and mechanism for the three-body mixed isospin calculations. We have studied the mechanism of the isospin mixing for 1 + , 2 + doublets in 8 Be and found a sharp sensitivity of isospin mixing to the experimentally not well defined parameters of the 3+1 intercluster interaction. The matrix elements of the β -decay of 8 B to 2 + doublet 16.6, 16.9 MeV were calculated and estimates were made for the probability of electron capture to 17.64 MeV state. It is found that about 90% of the Gamow–Teller (GT) sum rule is concentrated in the three-cluster 2 + and 1 + states, situated below the three-body thresholds, within narrow boundaries (16.5–19.0 MeV).

We present the results of test runs on a new system intended for the P-odd asymmetry measurement using the integral method of detecting events for the neutron polarization switching frequency (f) above the fundamental frequencies of the fluctuation power spectrum of a reactor. The dependence of the error of the P-odd asymmetry measurement in the γ quantum yield of the 10B(n, α)7Li* ⟹ γ ⟹ 7Li(g.s.) reaction on f has been studied. It is established for the first time that an increase in f leads to a sharp decrease in the error of asymmetry measurement for a single detector and, beginning with f ∼ 15 Hz, this error ceases to depend on the reactor power fluctuations.

Acta physica Polonica / B 45(2), 229 - 234 (2014). doi:10.5506/APhysPolB.45.229, Published by Inst. of Physics, Jagellonian Univ., Cracow

According to selection rules the β-decay of 8He 0g.s.+ to the first excited 1+, 0.98 MeV state of 8Li is an allowed Gamow-Teller transition, but it is strongly suppressed by the different SU(4) spin-isospin structure of the 8He and 8Li states. We find that a three-body α + t + n model of 8Li strongly underestimates the probability for β-decay (to the 8Li (0.98) state, 7 Li + n continuum and α + t + n continuum). A qualitative explanation of total BGT values, extracted from experiment, to different 1+ states can be given supposing an admixture of a “democratic” α + 4N configuration in the 8Li wave functions. We show that the experimental β-delayed neutron spectrum provides some evidence for the existence of 1− and/or 2− states in the vicinity of the two-body 7 Li + n and 7 Li ∗ (0.47) + n thresholds. Using the phase volume approximation to the analysis of the triton spectrum, the position of the Gamow-Teller resonance (Halo Analogue state) is estimated between 8.5 and 8.8 MeV excitation energy in the 8Li spectrum. One of the possibilities to excite this state could be the 6Li(6He,α)8He∗ reaction.

A three-body cluster 4He+t+n model is developed for 8Li using the method of hyperspherical harmonics with realistic cluster-cluster interactions fitted to experimental data. The model is used to calculate wave functions, spatial and matter densities of the ground state and the low lying excited state of 8Li. The model reproduces experimentally known properties of 8Li. Contrary to two-body models, our prediction for the radiative neutron capture on 7Li at low energies supports a lower cross section value.

In this paper we demonstrate an analytical model constructed in order to study electromagnetic processes involving loosely bound neutron-rich and proton-rich nuclei. The main feature is a model wave function, having the correct behaviour both at large and small distances. A pure Coulomb continuum is used. As a test case we consider the two-body electromagnetic dissociation of 8 B on a Pb target at 936 MeV/ A . We investigate the dependence of the 8 B dissociation cross section on the nuclear radius, for which we find a strong sensitivity.

6 pags., 5 figs. -- XII International Symposium on Nuclei in the Cosmos, August 5-12, 2012, Cairns, Australia, By the Coulomb breakup of 17Ne, the time-reversed reaction 15O(2p, γ) 17Ne has been studied. This reaction might play an important role in the rp process, as a break-out reaction of the hot CNO cycle. The secondary 17Ne ion beam with an energy of 500 MeV/nucleon has been dissociated in a Pb target. The reaction products have been detected with the LAND-R3B experimental setup at GSI. The preliminary differential and integral Coulomb dissociation cross section σCoul has been determined, which then will be converted into a photo-absorption cross section σphoto, and a two-proton radiative capture cross section σcap. Additionally, information about the structure of the 17Ne, a potential two-proton halo nucleus, will be received. The analysis is in progress., This project was supported by the German Federal Ministry for Education and Research (BMBF), EU(EURONS), EMMI-GSI, and HIC for FAIR

An installation for measuring parity violation in reactions with polarized neutrons involving the emission of secondary charged particles is described. The main part of the experimental setup is a multisection proportional chamber operated in the current mode. The 6Li(n,α)3H and 10B(n,α)7Li reactions are studied. The P-odd asymmetry was measured with an accuracy of δ ∼ 5 × 10−8.

A series of ultra-sensitive experiments has been carried out in 2001-2009 at the ILL measuring P -odd asymmetry in \( \gamma\) -quanta emission in the nuclear reaction 10B (n,\( \alpha\)) 7Li*\( \rightarrow\)\( \gamma\) + $7Li$(g.s.) with polarized cold neutrons. The resulting value of the asymmetry coefficient is \(\ensuremath \alpha_{P\mbox{-}{\rm odd}}= +(0.0 \pm 2.6_{{\rm stat}} \pm 1.1_{{\rm syst}}) \times 10^{-8}\) . These experiments profited from high-intensity PF1B neutron facility and a new version of the integral measuring method: for decreasing experimental uncertainties, the frequency of neutron spin-flip was higher than a typical reactor power noise frequency. Using the new value, we constrain the weak neutral current constant in the cluster model framework to \(\ensuremath f_{\pi}^{^{10}\rm B} \leq 0.6 \times 10^{-7}\) (at 90% c.l.). This constraint agrees with that following from the nuclear reaction 6Li (n,\( \alpha\)) 3H : \(\ensuremath f_{\pi}^{^{6}\rm Li} \leq 1.1 \times 10^{-7}\) (at 90% c.l.). However, they both contradict the “best” value in the quark model by Desplanques, Donoughe, and Holstein \(\ensuremath f_{\pi}^{{\rm DDH}}=4.6\cdot 10^{-7}\) . We invite experts in the field to contribute to the theoretical analysis of the problem.

Low-energy neutrino-induced reactions in 6 Li are investigated both in neutral and charged channels with special stress on 6 Li → α + 2N disintegration. Cross sections are calculated in the allowed approximation, with recoil effects being neglected. Wave functions in the continuum as well as in the discrete spectrum are exact solutions of the three-body Schrodinger equation. The possibility of 6 Li used as a low-energy (anti)neutrino detector is discussed.

The very exotic nuclear resonance systems, 10He and 13Li, are produced in proton-knockout reactions from relativistic beams of 11Li and 14Be. The experimentally determined energy and angular correlations between their decay products, He 8 + n + n and Li 11 + n + n , are analyzed using an expansion of decay amplitudes in a restricted set of hyperspherical harmonics. By considering only a small number of terms it is possible to extract the expansion coefficients directly from the experimental three-body correlations. This provides a model-independent way of getting information about the decay process, on the structure of the decaying nucleus and on the quantum characteristics of the binary subsystems. The results show that the He 8 + n + n relative-energy spectrum can be interpreted as consisting of two resonances, an I π = 0 + ground state and an excited I π = 2 + state. The Li 11 + n + n relative-energy spectrum is interpreted as an I π = 3 / 2 − ground state overlapping with excited states having a structure similar to the 2 + state in 10He but spread over several states due to the coupling to the I π = 3 / 2 − core. The 13Li data also give evidence for a contribution of a configuration where the two neutrons occupy the d-shell.

The renormalization of the axial-vector coupling constant λ = g A / g V , extracted from the neutron lifetime ( λ τ ) and from the neutron beta decay asymmetry ( λ c ) is considered carefully In the standard model of the electroweak interaction λ τ should be equal to λ c . According to recent experimental data on neutron beta decay, λ τ and λ c seem to differ from each other. This fact is explained in the framework of the manifestly left-right symmetric model SU(2) L × SU(2) R × U(1). The possibility of the existence of the right-handed current in the neutron beta decay is pointed out. A joint analysis of neutron beta decay and muon decay is performed, the right-handed current parameters are estimated. The axial-vector constant renormalization ( λ N ) by right-handed currents is evaluated.

The O-15(2p, gamma) Ne-17 reaction is studied using the time-reversed reaction of the Ne-17 E1 Coulomb dissociation on lead target in the context of nuclear astrophysics. Looking for the relation between the data on the Coulomb excitation and the astrophysical 2p-capture rate, one faces problem to extract the Coulomb E1 strength function from the measured Coulex cross section. We use a number of phenomenological approaches to estimate influence of such processes as Coulomb-nuclear interference, populations of states with different J(pi), etc. We calculate the Ne-17+ 2p astrophysical capture rate and compare the results with different calculations.

Electromagnetic processes in loosely bound nuclei are investigated using an analytical model. In particular, electromagnetic dissociation of $^8$B is studied and the results of our analytical model are compared to numerical calculations based on a three-body picture of the $^8$B bound state. The calculation of energy spectra is shown to be strongly model dependent. This is demonstrated by investigating the sensitivity to the rms intercluster distance, the few-body behavior, and the effects of final state interaction. In contrast, the fraction of the energy spectrum which can be attributed to E1 transitions is found to be almost model independent at small relative energies. This finding is of great importance for astrophysical applications as it provides us with a new tool to extract the E1 component from measured energy spectra. An additional, and independent, method is also proposed as it is demonstrated how two sets of experimental data, obtained with different beam energy and/or minimum impact parameter, can be used to extract the E1 component., Submitted to Phys. Rev. C. 10 pages, 7 figures

The structure and spectrum of the three-cluster states in 8Be around 16–20 MeV was studied in the framework of the hyperspherical harmonic method. For that purpose we have developed a potential formalism for T-p and 3He-n (3 + 1) scattering and mechanism for the three-body mixed isospin calculations. We have studied the mechanism of the isospin mixing for 1+,2+ doublets in 8Be and found a sharp sensitivity of isospin mixing to the experimentally not well defined parameters of the 3 + 1 intercluster interaction. The matrix elements of the β-decay of 8B to 2+ doublet 16.6, 16.9 MeV were calculated and estimates were made for the probability of electron capture to 17.64 MeV state. It is found that about 90% of the Gamow-Teller (GT) sum rule is concentrated in the three-cluster 2+ and 1+ states, situated below the three-body thresholds, within narrow boundaries (16.5–19.0 MeV).

Complete dynamical investigation of the extremely neutron rich 5H nucleus is performed in a three-body 3H + n + n continuum. A three-body resonance enhancement is found for the “ground state” J π = 1/2+ at about 2.5–3.0 MeV. The broad structures in the production cross-sections correspond to wide 3/2+ and 5/2+ levels in the three-body continuum.

One‐nucleon removal reactions at relativistic energies have been used as spectroscopic tool to obtain information about the ground state properties of 8B and 23O. Using the FRS at GSI, the longitudinal momentum distributions of the emerging fragments after breakup and the one‐nucleon removal cross‐sections were measured. The relative contributions of the remaining fragments (7Be and 22O) in their ground and excited states have been determined from measurements of γ rays in coincidence with the longitudinal momentum distributions. In the 8B case, the experimental breakup data on two different targets (C and Pb) allow a determination of the weight of the 7Be* component in the 8B ground state wave function as (13.3±2.2) %. These results are discussed in the context of a theoretical three‐body model. Preliminary results on 23O indicate a spin and parity assignment of 1/2+ in agreement with shell model predictions.

In this paper we develop an analytical model in order to study electromagnetic processes involving loosely bound neutron--rich and proton--rich nuclei. We construct a model wave function, to describe loosely bound few--body systems, having the correct behaviour both at large and small distances. The continuum states are approximated by regular Coulomb functions. As a test case we consider the two--body Coulomb dissociation of 8B and, the inverse, radiative capture reaction. The difference between using a pure two--body model and the results obtained when incorporating many--body effects, is investigated. We conclude that the interpretation of experimental data is highly model dependent and stress the importance of measuring few--body channels., Comment: Accepted for publication in Physics Letters B. Added a comparison with a potential model calculation in Fig. 2

The level structure of the unbound nucleus N-11 has been studied by C-10+p elastic resonance scattering in inverse geometry with the LISE3 spectrometer at GANIL, using a C-10 beam with an energy of 9.0 MeV/ nucleon. An additional measurement was done at the A1200 spectrometer at MSU. The excitation function above the C-10+p threshold has been determined up to 5 MeV. A potential-model analysis revealed three resonance states at energies 1.27(-0.05)(+0.18) MeV (Gamma = 1.44 +/- 0.2 MeV), 2.01(-0.05)(+0.15) MeV (Gamma = 0.84 +/- 0.2 MeV), and 3.75 +/- 0.05 MeV (Gamma = 0.60 +/- 0.05 MeV) with the spin-parity assignments I-pi=1/2+,1/2,-,5/2+, respectively. Hence, N-11 is shown to have a ground state parity inversion completely analogous to its mirror partner Be-11. A narrow resonance in the excitation function at 4.33 +/- 0.05 MeV was also observed and assigned spin parity 3/2-.

Complete dynamical investigation of the extremely neutron-rich ${}^{5}\mathrm{H}$ nucleus is performed in a three-body ${}^{3}\mathrm{H}+n+n$ continuum. A three-body resonance enhancement is found for the ``ground state'' ${J}^{\ensuremath{\pi}}{=1/2}^{+}$ at about 2.5--3.0 MeV. The broad structures in the production cross sections correspond to wide ${3/2}^{+}$ and ${5/2}^{+}$ levels in the three-body continuum.

The results of measuring the P-odd asymmetry (Sn · Pt) for triton emission from the reaction 6Li(n, α)3H are presented. Here, Sn is the neutron spin and Pt is the triton momentum. Three series of measurements were performed, one at the Petersburg Nuclear Physics Institute (Gatchina, Russia) in a vertical neutron beam from the PWR reactor and two in the PF1B beam from the reactor at the Institute Laue-Langevin (Grenoble, France). On the basis of all three experiments, the P-odd asymmetry coefficient was found to be αPN = −(8.6 ± 2.0) × 10−8. The results of zero experiments and calculations give every reason to believe that the above P-odd asymmetry is due to the reaction being studied.

The contributions of the highest SU(4) Casimir operators in SU(4) mass formula are investigated for the A ≧ 216 region based on a hypothesis of the restoration of Wigner symmetry with increasing N − Z and on experimental mass-difference data. The experimental estimates for three- and four-body force terms in the modified mass formula are found. The experimental differences of the isobar masses in this region are described with an accuracy near 200 keV.

An installation using a light-water neutron trap in the reactor core as a proton target is described. Results of the main and control measurements are presented which permit one to conclude that the parity-violating circular polarization of the γ-rays from the np → dγ reaction is Pγ = (1.8 ± 1.8) × 10−7.

En la formación del clima intervienen una serie de procesosos muy complejos que interaccionan en el sistema "atmósfera-océano-continentes-criósfera". el problema de clima y sus cambios originados naturalmente y por factores antropogénicos exige el seguimiento de un amplio conjunto de parámetros que caractericen no sólo al clima sino los rasgos propios de la atmósfera, océano, superficie terrestre y cubierta de hielo.La determinación del conjunto de parámetros requerido debe obtenerse a partir del modelado numérico dirigido a la planeación del sistema global para monitoreo del clima. Las restricciones sobre los datos observacionales son muy variables y fuertemente dependientes del modelo del clima utilizado. en base a estas consideraciones se presenta una estimación de los parámetros requeridos que integran el conjunto, se incluye precisión y resolución espacio-temporal. Se analizan las posibilidades de medición por los sistemas actuales, los ya diseñados y lo que se desarrollarán en los años ochentas. Finalmente, se evalúan los errores que se cometen utilizando microondas en la determinación de la temperatura de la cubierta de hielo y de la superficie del mar.